Research
L-Citrulline
82 peer-reviewed studies curated from PubMed and Semantic Scholar.
Studies
Sorted by quality and recency
Does l-citrulline supplementation and watermelon intake reduce blood pressure in middle-aged and older adults? A systematic review and meta-analysis of randomized controlled trials.
This systematic review and meta-analysis of 15 RCTs with 415 participants examined the effects of l-citrulline supplementation and watermelon intake on blood pressure in middle-aged and elderly individuals. The study found that both interventions significantly reduced systolic and diastolic blood pressure, with combined l-citrulline and l-arginine supplementation showing superior effects.
Effects of L-citrulline supplementation and watermelon intake on arterial stiffness and endothelial function in middle-aged and older adults: a systematic review and meta-analysis of randomized controlled trials.
Systematic review and meta-analysis of 8 RCTs with 176 participants examining the effects of L-citrulline supplementation and watermelon intake on arterial stiffness and endothelial function in middle-aged and older adults. L-citrulline significantly improved flow-mediated dilation (FMD) and reduced ankle-brachial pulse wave velocity (BA-PWV), suggesting potential cardiovascular benefits. Watermelon intake did not significantly improve FMD or PWV.
Effects of Citrulline or Watermelon Supplementation on Body Composition: A Systematic Review and Dose–Response Meta-Analysis
Systematic review and dose–response meta-analysis of 21 RCTs assessing the impact of citrulline supplementation on body composition. Overall, citrulline had no substantial effects on BMI, body weight, fat mass, waist circumference, body fat percentage, and fat-free mass. Subgroup analyses showed reductions in fat mass among participants over 40 and those taking more than 6 g/day, with interventions of 3 to 8 weeks increasing fat-free mass.
Effect of citrulline on post-exercise rating of perceived exertion, muscle soreness, and blood lactate levels: A systematic review and meta-analysis.
Systematic review and meta-analysis of 13 RCTs with 206 participants examining citrulline supplementation's effects on post-exercise outcomes. Citrulline significantly reduced post-exercise rating of perceived exertion and muscle soreness but did not affect blood lactate levels.
Effects of Citrulline Supplementation on Exercise Performance in Humans: A Review of the Current Literature.
Systematic review of the effects of L-citrulline supplementation on exercise performance and recovery in humans. The review discusses the potential ergogenic properties of L-citrulline, its impact on vascular function, and its synergistic effects with other dietary ingredients. While evidence for acute improvements in vasodilation is inconsistent, several studies report enhanced exercise performance and recovery.
The Antioxidant Power of Bergamot Polyphenolic Fraction Gold Potentiates the Effects of L-Citrulline in Athlete Performance and Vasodilation in a Pilot Study.
A randomized, double-blind, placebo-controlled pilot trial investigated the effects of L-citrulline and Bergamot Polyphenolic Fraction Gold (BPFG) on athletic performance and blood flow in 90 male cyclists. The combination significantly increased nitric oxide release, reactive vasodilation, and cardiorespiratory fitness, with no adverse effects observed.
Oral citrulline supplementation in pregnancies with preeclampsia: a multicenter, randomized, double-blind clinical trial.
A multicenter, randomized, double-blind trial with 115 preeclamptic pregnant women tested oral L-citrulline supplementation. The study found no benefit in prolonging pregnancy duration or improving maternal and neonatal outcomes. Systolic blood pressure and liver enzyme levels increased at delivery in the citrulline group.
Enteral citrulline supplementation versus placebo on SOFA score on day 7 in mechanically ventilated critically ill patients: the IMMUNOCITRE randomized clinical trial.
A randomized, double-blind, multicenter clinical trial evaluated enteral L-citrulline administration versus placebo in 120 mechanically ventilated ICU patients. The primary outcome, SOFA score on day 7, showed no significant difference between groups. Plasma arginine increased in the treatment group, but immune parameters were unaffected.
Sex May Modulate the Effects of Combined Polyphenol Extract and L-citrulline Supplementation on Ambulatory Blood Pressure in Adults with Prehypertension: A Randomized Controlled Trial.
RCT of 73 adults with prehypertension comparing placebo to supplementation with polyphenol extract and L-citrulline for 6 weeks. The supplement had no overall impact on ambulatory BP, blood lipids, and CRP, but reduced ambulatory SBP in women, not in men, indicating a potential sex-dependent response.
The effects of citrulline supplementation on meta-inflammation and insulin sensitivity in type 2 diabetes: a randomized, double-blind, placebo-controlled trial
This randomized, double-blind, placebo-controlled trial studied the effects of l-citrulline supplementation on meta-inflammation and insulin sensitivity in 54 type 2 diabetes patients. l-Citrulline significantly reduced fasting blood glucose and HbA1c levels but did not significantly improve insulin sensitivity or meta-inflammation biomarkers.
Oxidative stress and nitrate/nitrite (NOx) status following citrulline supplementation in type 2 diabetes: a randomised, double-blind, placebo-controlled trial.
This double-blind, placebo-controlled RCT studied the effects of citrulline supplementation on oxidative stress and nitrate/nitrite status in 54 patients with type 2 diabetes. Citrulline supplementation significantly decreased serum levels of fasting blood sugar and malondialdehyde, and increased total antioxidant capacity, citrulline, and NOx levels compared to placebo.
Effect of L-Citrulline Supplementation on Blood Pressure: a Systematic Review and Meta-Analysis of Clinical Trials.
Systematic review and meta-analysis of clinical trials assessing the effect of L-citrulline supplementation on blood pressure. The analysis included five interventions and found no significant impact on brachial or aortic systolic and diastolic blood pressure. Participants' body weight status contributed to heterogeneity.
Impact of L-Citrulline Supplementation and HIIT on Lipid Profile, Arterial Stiffness, and Fat Mass in Obese Adolescents with Metabolic-Dysfunction-Associated Fatty Liver Disease: A Randomized Clinical Trial.
This randomized clinical trial evaluated the effects of L-citrulline supplementation and high-intensity interval training (HIIT) on arterial stiffness, body composition, glucose metabolism, lipid profile, and blood pressure in 44 obese adolescents with metabolic-dysfunction-associated steatotic liver disease. HIIT combined with L-citrulline improved lipid profiles and cardiorespiratory fitness, while L-citrulline alone decreased hepatic steatosis.
Combined Vs. Single Supplementation of L-Citrulline and Sodium Bicarbonate During Sprint Interval Training in Basketball Players: Effects on Physical Performance and Hormonal Adaptations.
RCT examining the effects of L-citrulline and sodium bicarbonate supplementation during sprint interval training in 40 male basketball players over 28 days. Supplement groups showed significant improvements in physical performance and lower cortisol levels compared to placebo, but no significant changes in testosterone.
Changes in resistance training performance, rating of perceived exertion, and blood biomarkers after six weeks of supplementation with L-citrulline vs. L-citrulline DL-malate in resistance-trained men: a double-blind placebo-controlled trial.
This double-blind placebo-controlled trial investigated the effects of L-Citrulline and L-Citrulline DL-malate supplementation on resistance training performance in 33 resistance-trained men over six weeks. The study found that both forms of citrulline enhanced upper body muscular endurance and post-exercise nitric oxide response, with no significant differences between the two forms.
Effects of L-Citrulline Supplementation on Endothelial Function, Arterial Stiffness, and Blood Glucose Level in the Fasted and Acute Hyperglycemic States in Middle-Aged and Older Adults with Type 2 Diabetes.
RCT of 16 middle-aged and older adults with type 2 diabetes mellitus assessing the effects of L-citrulline supplementation (6 g/day) for 4 weeks. L-citrulline improved endothelial function, arterial stiffness, and blood glucose levels in both fasted and acute hyperglycemic states compared to placebo.
Malate or Not? Acute Effects of L-Citrulline Versus Citrulline Malate on Neuromuscular Performance in Young, Trained Adults: A Randomized, Double-Blind, Placebo-Controlled Crossover Trial.
This randomized, double-blind, placebo-controlled crossover trial compared the acute effects of L-citrulline versus citrulline malate supplementation on neuromuscular performance in young, trained adults. The study found that neither L-citrulline nor citrulline malate supplementation enhanced maximal neuromuscular performance, ballistic strength, strength-endurance, or exertion and emotional perceptions during resistance training sessions.
L-Citrulline Supplementation Improves Arterial Blood Flow and Muscle Oxygenation during Handgrip Exercise in Hypertensive Postmenopausal Women.
RCT of 22 hypertensive postmenopausal women examining the effects of 10 g/day L-Citrulline supplementation for 4 weeks. L-Citrulline significantly improved endothelial function, arterial vasodilation, and muscle oxygenation during exercise compared to placebo.
Enteral L-citrulline supplementation in preterm infants is safe and effective in increasing plasma arginine and citrulline levels-a pilot randomized trial.
This pilot randomized trial studied enteral L-citrulline supplementation in 42 preterm infants. The study found that supplementation was safe and effective in significantly increasing plasma citrulline and arginine levels, with no adverse events reported.
CHronic hypERtension and L-citRulline studY (CHERRY): an Early-Phase Randomised Controlled Trial in Pregnancy.
This early-phase randomised feasibility trial assessed the acceptability of L-citrulline supplementation in pregnant women with chronic hypertension and its effects on maternal blood pressure and vascular outcomes. L-citrulline supplementation increased maternal plasma levels of citrulline, arginine, and the arginine:asymmetric dimethylarginine ratio, but had no significant effect on diastolic blood pressure or other vascular biomarkers. The study was underpowered to detect blood pressure changes less than 9 mmHg.
Effects of branched chain amino acids, l-citrulline, and alpha-glycerylphosphorylcholine supplementation on exercise performance in trained cyclists: a randomized crossover trial.
Randomized crossover trial with 30 male trained cyclists testing the effects of BCAAs, L-citrulline, and A-GPC supplementation on exercise performance. The supplement significantly increased peak power in a 20 km time trial and time to fatigue in a high intensity endurance cycling test compared to placebo.
The effects of L-Citrulline and Glutathione on Endurance performance in young adult trained males.
This randomized, double-blind, placebo-controlled crossover study investigated the effects of L-citrulline and Glutathione on aerobic exercise performance and blood flow in 25 well-trained men. Results showed that blood flow and L-citrulline and L-arginine plasma concentrations were significantly elevated after high-intensity exercise with the supplement compared to placebo, suggesting enhanced performance.
L-Citrulline supplementation attenuates aortic pressure and pressure waves during metaboreflex activation in postmenopausal women.
RCT investigating the effects of L-Citrulline supplementation on aortic systolic blood pressure, pulse pressure, and pressure wave responses during isometric handgrip exercise and postexercise muscle ischaemia in 22 postmenopausal women. L-Citrulline attenuated increases in aortic pulsatile load by reducing forward and backward pressure wave amplitudes.
Short-Term L-Citrulline Supplementation Does Not Affect Inspiratory Muscle Oxygenation and Respiratory Performance in Older Adults.
This study examined the effect of short-term L-citrulline supplementation on respiratory muscle performance, fatigue, and oxygenation in 14 healthy older males. While L-citrulline increased exhaled nitric oxide, it did not affect pulmonary function, maximal inspiratory pressure, rate of perceived exertion, or muscle oxygenation.
L-Citrulline supplementation attenuates aortic pulse pressure and wave reflection responses to cold stress in older adults.
RCT with 16 older adults in a crossover, double-blind, placebo-controlled design to test L-citrulline supplementation (6g/day for 14 days) on aortic hemodynamic responses to cold pressor test. L-citrulline significantly attenuated brachial and aortic SBP, pulse pressure, and wave reflection responses, suggesting potential cardioprotection during cold-induced sympathoactivation.
Acute Citrulline Blunts Aortic Systolic Pressure during Exercise and Sympathoactivation in Hypertensive Postmenopausal Women.
RCT involving 15 hypertensive postmenopausal women examining the effects of 6g l-citrulline supplementation versus placebo on aortic systolic blood pressure during exercise and cold pressor test. Acute l-citrulline ingestion attenuated aortic SBP response, potentially preventing left ventricle overload.
Effect of watermelon supplementation on exercise performance, muscle oxygenation, and vessel diameter in resistance-trained men.
RCT with 15 resistance-trained men examining the effect of watermelon supplementation on exercise performance, muscle oxygenation, and vessel diameter. Results showed no significant enhancement in isometric force production, bench press performance, blood vessel diameter, or muscle oxygenation compared to placebo.
Eight Days of L-Citrulline or L-Arginine Supplementation Did Not Improve 200-m and 100-m Swimming Time Trials.
RCT assessing the effects of 8-day supplementation with L-arginine or L-citrulline on 200 m and 100 m freestyle swimming time-trial performances in 15 trained/developmental swimmers and triathletes. No significant improvement in swimming performance was observed with supplementation.
The impact of L-citrulline supplementation on glucose homeostasis, lipid profile, and some inflammatory factors in overweight and obese patients with type 2 diabetes: A double-blind randomized placebo-controlled trial.
This double-blind randomized placebo-controlled trial investigated the impact of L-citrulline supplementation on glucose homeostasis, lipid profile, and inflammatory factors in overweight and obese patients with type 2 diabetes. L-citrulline supplementation significantly decreased serum levels of insulin, glucose, HbA1c, HOMA-IR, TNF-α, and hs-CRP. Improvements were noted in glucose homeostasis and some lipid and inflammatory markers.
L-Citrulline Supplementation and Exercise in the Management of Sarcopenia.
RCT of 44 participants aged 60-73 testing citrulline supplementation alongside a physical activity program. The citrulline group showed significant improvement in walking speed compared to placebo, with tendencies for improved strength and endurance.
Treatment with L-Citrulline in patients with post-polio syndrome: A single center, randomized, double blind, placebo-controlled trial.
This single-centered, randomized, double-blind, placebo-controlled study evaluated L-Citrulline treatment for 24 weeks in patients with post-polio syndrome. The primary endpoint was the change in the 6-minute walking distance test, which showed no statistically significant improvement. Secondary endpoints, including motor function measure and muscle strength, also showed no significant changes. L-Citrulline was safe and well tolerated.
Acute L-Citrulline Supplementation Increases Nitric Oxide Bioavailability but Not Inspiratory Muscle Oxygenation and Respiratory Performance.
This study investigated the effects of acute L-citrulline supplementation on inspiratory muscle oxygenation and respiratory performance in 12 healthy males. While L-citrulline increased nitric oxide bioavailability, it did not affect respiratory performance or inspiratory muscle oxygenation.
The Effects of L-Citrulline on Blood-Lactate Removal Kinetics Following Maximal-Effort Exercise.
Double-blind, randomized, placebo-controlled study on the effects of L-citrulline on blood lactate removal kinetics during active recovery in healthy university students. L-citrulline supplementation did not significantly alter blood lactate kinetics, oxygen cost of exercise, V̇O2peak, or time-to-exhaustion.
Response of exercise-onset vasodilator kinetics to L-citrulline supplementation during different phases of the menstrual cycle.
This study investigated the effects of L-citrulline supplementation on vasodilator kinetics during exercise in women across different menstrual cycle phases. Twenty-four women participated in a crossover design study, receiving either L-citrulline or placebo. The study found no significant differences in vasodilator kinetics between L-citrulline and placebo or between menstrual cycle phases.
One Week of L-Citrulline Supplementation Improves Performance in Trained Cyclists.
This randomized, double-blind, crossover study tested the effects of L-citrulline supplementation on cycling performance in nine trained male cyclists. Over a 7-day period, L-citrulline supplementation improved time trial performance by 5.2% and increased average heart rate, perceived exertion, and power, though it did not prevent fatigue during a supramaximal sprint task.
Effects of L-citrulline supplementation on blood pressure: A systematic review and meta-analysis
Systematic review and meta-analysis of clinical trials examining the effects of L-citrulline supplementation on blood pressure. The analysis included 8 trials with 10 data sets, showing that L-citrulline may reduce systolic BP, with significant diastolic BP reduction observed in studies using doses ≥6 g/day.
[The effect of supplementation with L-arginine and L-citrulline on physical performance: a systematic review].
Systematic review of 38 articles analyzing the effect of L-arginine and L-citrulline supplementation on physical performance. L-citrulline showed a positive effect on perceived exertion, muscular pain, lactate concentrations, and time in maximum tests, while L-arginine was less effective.
Measurements of Motor Function and Other Clinical Outcome Parameters in Ambulant Children with Duchenne Muscular Dystrophy.
The study presents clinical and radiological outcome measures used in ambulatory patients with Duchenne muscular dystrophy participating in a trial of L-citrulline and metformin. It highlights the use of motor function measures, timed functional tests, and quantitative MRI to monitor changes in muscle function and disease progression.
Effect of High-Intensity Interval Training Combined with L-Citrulline Supplementation on Functional Capacities and Muscle Function in Dynapenic-Obese Older Adults
RCT comparing high-intensity interval training (HIIT) alone versus HIIT combined with L-citrulline supplementation in 56 dynapenic-obese older adults. The HIIT+CIT group showed greater improvements in fast-paced Timed Up & Go and upper limbs muscle strength compared to HIIT+Placebo.
Combined L-citrulline and glutathione supplementation increases the concentration of markers indicative of nitric oxide synthesis.
The study evaluated the effects of L-citrulline and glutathione supplementation on nitric oxide synthesis markers in vitro, in rodents, and in humans. Results showed that combining L-citrulline with glutathione significantly increased nitrite and NOx levels in both in vitro and in vivo conditions.
Effect of Combination l-Citrulline and Metformin Treatment on Motor Function in Patients With Duchenne Muscular Dystrophy: A Randomized Clinical Trial.
A randomized clinical trial evaluated the effects of l-citrulline and metformin combination therapy on motor function in 47 male patients with Duchenne muscular dystrophy. The study found no significant overall reduction in motor function decline, but a reduction was observed in the stable subgroup. The treatment was well tolerated with mild adverse effects.
L-Citrulline increases nitric oxide and improves control in obese asthmatics.
Open-label pilot study of 41 obese asthmatics assessing the effects of 15 g/d L-citrulline for 2 weeks. L-citrulline increased fractional excretion of NO and improved asthma control, with larger FEV1 increments observed in late-onset asthma and females.
A combination of oral L-citrulline and L-arginine improved 10-min full-power cycling test performance in male collegiate soccer players: a randomized crossover trial.
A randomized crossover trial with 24 male soccer players tested the effects of oral L-citrulline and L-arginine on cycling performance. The combination improved 10-min cycling power output and subjective perception of exertion compared to placebo.
Impact of l-citrulline supplementation on oxygen uptake kinetics during walking.
Randomized, double-blind crossover study of 26 adults (15 women, 11 men) aged 20-35 and 64-86 years, examining the effects of l-citrulline supplementation on oxygen uptake kinetics during walking. L-citrulline improved the rate of rise in oxygen uptake at exercise onset in men but did not alter the oxygen cost of moderate-intensity walking in young or older adults.
Effects of single and combined metformin and L-citrulline supplementation on L-arginine-related pathways in Becker muscular dystrophy patients: possible biochemical and clinical implications.
RCT investigating the effects of L-citrulline supplementation and metformin treatment on L-arginine-related pathways in 20 male Becker muscular dystrophy patients. L-citrulline increased amino acid and creatinine concentrations, while metformin decreased arginine and oxidative stress biomarkers. Combined use attenuated effects of single administrations.
The Assessment of short-term effect of L-Citrulline on endothelial function via FMD to NMD ratio in known CAD patients: A randomized, cross-over clinical trial (Clinical trial number: NCT02638727).
This cross-over clinical trial assessed the effect of L-Citrulline on endothelial function in 30 CAD patients. L-Citrulline administration significantly improved the FMD to NMD ratio and FMD value compared to placebo, indicating enhanced endothelial function.
Does l-citrulline supplementation improve exercise blood flow in older adults?
RCT investigating the effects of l-citrulline supplementation on exercise blood flow in older adults. l-Citrulline increased femoral blood flow and vascular conductance during exercise in older men, but not in women, suggesting a modest improvement in muscle blood flow and potential enhancement of exercise tolerance.
Consumption of Watermelon Juice Enriched in l-Citrulline and Pomegranate Ellagitannins Enhanced Metabolism during Physical Exercise.
A double-blind randomized crossover study in 19 healthy male subjects examined the effects of watermelon juice enriched with l-citrulline and pomegranate ellagitannins on exercise performance. The enriched juice maintained basal levels of muscle damage markers and improved force maintenance, perceived exertion, and muscle soreness during and after high-intensity exercise.
Treatment with L-citrulline and metformin in Duchenne muscular dystrophy: study protocol for a single-centre, randomised, placebo-controlled trial.
This randomised, double-blind, placebo-controlled trial aims to demonstrate the superiority of L-citrulline and metformin therapy over placebo in Duchenne muscular dystrophy (DMD) patients. The primary endpoint is the change of the Motor Function Measure (MFM) D1 subscore from baseline to week 26. Secondary endpoints include various motor function tests and muscle MRI assessments.
Oral L-citrulline supplementation enhances cycling time trial performance in healthy trained men: Double-blind randomized placebo-controlled 2-way crossover study
Double-blind randomized placebo-controlled 2-way crossover study of 22 trained males taking 2.4g/day of L-citrulline for 7 days. L-citrulline supplementation significantly increased plasma L-arginine levels, reduced cycling time trial completion time by 1.5%, and improved subjective feelings of muscle fatigue and concentration.
l-Citrulline supplementation attenuates blood pressure, wave reflection and arterial stiffness responses to metaboreflex and cold stress in overweight men.
RCT with 16 overweight/obese males examining the effects of l-citrulline supplementation on aortic haemodynamic and arterial stiffness responses to exercise and cold stress. l-Citrulline attenuated increases in aortic blood pressure and wave reflection during stress tests, suggesting a protective effect against increased cardiac afterload.
Impact of L-citrulline supplementation and whole-body vibration training on arterial stiffness and leg muscle function in obese postmenopausal women with high blood pressure.
RCT investigating the effects of whole-body vibration training (WBVT) and L-citrulline supplementation on arterial stiffness and muscle function in 41 obese postmenopausal women. WBVT + L-citrulline decreased aortic stiffness and increased leg muscle mass index more than either intervention alone, suggesting enhanced cardiovascular and muscle function benefits.
Combined whole-body vibration training and l-citrulline supplementation improves pressure wave reflection in obese postmenopausal women.
RCT of 41 obese postmenopausal women randomized to l-citrulline, WBVT+l-citrulline, and WBVT+Placebo groups for 8 weeks. All groups decreased brachial and aortic pressures and increased NOx levels. AIx and AIx@75 decreased in WBVT+l-citrulline and WBVT+Placebo groups, but not in the l-citrulline group alone. The combined intervention reduced AIx@75 significantly compared to l-citrulline alone.
l-Citrulline supplementation improves O2 uptake kinetics and high-intensity exercise performance in humans.
Randomized, placebo-controlled, crossover study comparing l-citrulline and l-arginine supplementation on nitric oxide biomarkers, O2 uptake kinetics, and exercise performance in 10 healthy men. l-Citrulline improved blood pressure, O2 uptake kinetics, and exercise performance, while l-arginine did not show significant effects.
The effect of l-citrulline and watermelon juice supplementation on anaerobic and aerobic exercise performance.
Randomized double-blind study with 22 participants examining the effects of a single pre-exercise dose of l-citrulline, watermelon juice, or placebo on exercise performance metrics. No significant effects were found for total repetitions, time to exhaustion, VO2max, anaerobic threshold, or flow-mediated vasodilation.
Effects of watermelon supplementation on aortic hemodynamic responses to the cold pressor test in obese hypertensive adults.
RCT assessing the effect of L-citrulline-rich watermelon supplementation on aortic hemodynamic responses to the cold pressor test in obese hypertensive adults. Watermelon reduced brachial and aortic systolic blood pressure and myocardial oxygen demand during the test, suggesting potential cardioprotective effects.
Effects of Oral L-Citrulline Supplementation on Lipoprotein Oxidation and Endothelial Dysfunction in Humans with Vasospastic Angina
RCT of 22 patients with vasospastic angina receiving 800 mg/day of L-citrulline for 8 weeks. L-citrulline supplementation improved endothelial dysfunction, increased NOx levels, and reduced serum oxidized LDL and LOX-1 ligand levels.
Effects of watermelon supplementation on arterial stiffness and wave reflection amplitude in postmenopausal women.
Randomized cross-over study of 12 postmenopausal women examining the effects of L-citrulline-rich watermelon supplementation on arterial stiffness and wave reflection. Watermelon supplementation reduced arterial stiffness and aortic systolic blood pressure by decreasing pressure wave reflection amplitude.
Improvement of ventricular function in systolic heart failure patients with oral L-citrulline supplementation.
RCT evaluating the effect of oral L-citrulline supplementation (3 g/day) on ventricular function in 35 systolic heart failure patients over 4 months. L-citrulline significantly improved left and right ventricular ejection fractions, functional class, and endothelial function compared to control.
The effects of short term L-citrulline supplementation on wave reflection responses to cold exposure with concurrent isometric exercise.
RCT with 16 healthy males studying the effects of L-citrulline supplementation on blood pressure and pulse-wave-reflection responses during cold exposure and isometric exercise. L-citrulline decreased brachial and aortic systolic blood pressure and augmentation index at rest, but did not affect responses during exercise.
The effect of L-citrulline ingestion on ECG QT interval and autonomic nervous system activity.
RCT investigating the effect of L-citrulline ingestion on ECG QT interval in nine healthy male subjects. L-citrulline ingestion significantly decreased the heart-rate-corrected QT interval 60 and 90 minutes post-ingestion, suggesting it may shorten myocardial depolarization and repolarization time.
Short-term effects of L-citrulline supplementation on arterial stiffness in middle-aged men.
Double-blind, randomized, placebo-controlled trial of 15 healthy middle-aged men examining the effects of 5.6g/day L-citrulline supplementation on arterial stiffness over 7 days. L-citrulline significantly reduced brachial-ankle pulse wave velocity compared to placebo, indicating improved arterial stiffness, independent of blood pressure.
Effects of watermelon supplementation on aortic blood pressure and wave reflection in individuals with prehypertension: a pilot study.
This pilot study evaluated the effects of watermelon supplementation on aortic blood pressure and arterial function in nine individuals with prehypertension. Watermelon supplementation significantly improved aortic hemodynamics, reducing brachial pulse pressure, aortic systolic blood pressure, aortic pulse pressure, and augmentation index.
Effects of L-citrulline oral supplementation on polymorphonuclear neutrophils oxidative burst and nitric oxide production after exercise.
RCT with 17 male professional cyclists examining the effects of 6 g L-citrulline-malate supplementation. Citrulline increased plasma arginine and citrulline levels, enhanced PMNs oxidative burst post-exercise, and increased PMN nitrite concentration without causing oxidative damage.
Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolism.
Double-blind, randomized, placebo-controlled cross-over study in 20 healthy volunteers assessing the pharmacokinetic and pharmacodynamic effects of oral L-citrulline and L-arginine. L-Citrulline increased plasma L-arginine concentration and augmented NO-dependent signaling more effectively than L-arginine. No improvement in flow-mediated vasodilation was observed.
Oral citrulline as arginine precursor may be beneficial in sickle cell disease: early phase two results.
Phase II clinical trial of oral L-citrulline supplementation in children and adolescents with sickle cell disease. The study found improvements in symptoms of well-being, increased plasma arginine levels, and reductions in leukocyte and neutrophil counts. No side effects or toxicity were reported.
Improved vascular function and functional capacity following l-citrulline administration in patients with heart failure with preserved ejection fraction: a single-arm, open-label, prospective pilot study.
A single-arm, open-label, prospective pilot study evaluated the impact of enteral l-citrulline (6 g/day for 7 days) on vascular function and functional capacity in 14 patients with heart failure with preserved ejection fraction. Improvements were observed in flow-mediated dilation, reactive hyperemia, passive limb movement, and 6-minute walk test distance, along with increased plasma l-citrulline and l-arginine levels.
L-Citrulline Supplementation Increases Plasma Nitric Oxide Levels and Reduces Arginase Activity in Patients With Type 2 Diabetes
The study investigated the effects of L-citrulline supplementation on plasma nitric oxide levels and arginase activity in patients with type 2 diabetes. L-citrulline supplementation (2000 mg/day for 1 month) decreased arginase activity by 21% and increased plasma NO levels by 38% in T2DM patients, suggesting potential therapeutic benefits for vascular function.
L-citrulline production by metabolically engineered Corynebacterium glutamicum from glucose and alternative carbon sources
The study involves metabolic engineering of Corynebacterium glutamicum to overproduce L-citrulline from glucose and alternative carbon sources. The engineered strain accumulated significant amounts of L-citrulline, demonstrating production from starch, xylose, and glucosamine.
Citrulline, Biomarker of Enterocyte Functional Mass and Dietary Supplement. Metabolism, Transport, and Current Evidence for Clinical Use
Narrative review discussing L-citrulline as a biomarker for intestinal integrity and its potential use as a therapeutic supplement. The paper covers citrulline's properties, functions, and evidence for its clinical use.
L-Citrulline: A Non-Essential Amino Acid with Important Roles in Human Health
This narrative review explores the roles of L-citrulline, including its synthesis, metabolism, and effects on exercise performance, cardiovascular diseases, diabetes, erectile dysfunction, and cancer. It highlights L-citrulline's potential as a natural alternative to pharmacological products, particularly from sources like watermelon.
Effects of L-Citrulline Supplementation and Aerobic Training on Vascular Function in Individuals with Obesity across the Lifespan
This narrative review examines the efficacy of L-Citrulline supplementation and aerobic training on vascular and metabolic parameters in obese individuals. The combination of L-Citrulline and exercise is suggested to improve endothelial function, blood pressure, arterial stiffness, and metabolic health.
Administration of L-arginine plus L-citrulline or L-citrulline alone successfully retarded endothelial senescence
The study investigated the effects of L-citrulline and L-arginine supplementation on endothelial function, aging, and atherosclerosis. In both human endothelial cells and dyslipidemic type 2 diabetic rats, L-citrulline and its combination with L-arginine retarded high glucose-induced endothelial senescence, improved nitric oxide production, and reduced oxidative stress markers.
Evaluation of the Effects and Mechanism of L-Citrulline on Anti-obesity by Appetite Suppression in Obese/Diabetic KK-Ay Mice and High-Fat Diet Fed SD Rats.
The study investigated the effects of L-Citrulline on anti-obesity in obese/diabetic KK-Ay mice and high-fat diet fed SD rats. L-Citrulline significantly reduced food intake, body weight, and fat tissue mass in mice, and showed similar effects in rats. It also improved glucose and fatty metabolism, suggesting benefits for metabolic syndrome through appetite suppression.
Two weeks of watermelon juice supplementation improves nitric oxide bioavailability but not endurance exercise performance in humans.
This study tested the effects of 16 days of watermelon juice supplementation on nitric oxide bioavailability and exercise performance in 8 healthy males. Watermelon juice increased plasma [l-citrulline], [l-arginine], and [nitrite], and improved muscle oxygenation during moderate-intensity exercise, but did not improve time-to-exhaustion during severe-intensity exercise and increased resting blood pressure.
L-Citrulline Protects Skeletal Muscle Cells from Cachectic Stimuli through an iNOS-Dependent Mechanism
In vitro study on the effects of L-citrulline on skeletal muscle cells under catabolic conditions. L-citrulline improved protein synthesis rates and myotube diameter, and increased iNOS mRNA expression, suggesting a protective effect against muscle wasting.
Oral supplementation with a combination of L-citrulline and L-arginine rapidly increases plasma L-arginine concentration and enhances NO bioavailability.
Animal study investigating the acute effects of oral L-citrulline and L-arginine supplementation on plasma L-arginine and NO levels. The combination rapidly increased plasma L-arginine levels and enhanced NO bioavailability, improving blood flow in the central ear artery of rabbits.
l-Citrulline Protects from Kidney Damage in Type 1 Diabetic Mice
The study investigates the effects of l-citrulline supplementation on diabetic nephropathy in type 1 diabetic mice and rats. l-Citrulline showed protective effects on kidney function, reduced urinary albumin excretion, and established an anti-inflammatory profile, characterized by increased IL-10 and reduced IL-1β and IL-12(p70) in human proximal tubular cells.
l-Citrulline Supplementation: Impact on Cardiometabolic Health
This narrative review examines the impact of l-citrulline supplementation on cardiovascular and metabolic health outcomes. It highlights l-citrulline's effectiveness in increasing nitric oxide synthesis, lowering blood pressure, and providing atherogenic-endothelial protection, with potential benefits for muscle and metabolic health in older populations.
Citrulline in health and disease. Review on human studies.
Narrative review on the use of L-citrulline in health and disease, highlighting its potential therapeutic roles in urea cycle defects, cardiovascular diseases, and disease-related malnutrition. Citrulline is efficiently recycled into endothelial and immune cells and may prevent excessive nitric oxide production, with positive effects on protein synthesis mediated through the mTOR pathway.
Arginine and citrulline for the treatment of MELAS syndrome.
The paper discusses the potential therapeutic utility of L-arginine and L-citrulline supplementation in MELAS syndrome, a mitochondrial disease. It highlights the role of nitric oxide deficiency in the disease and suggests that L-citrulline may have a better therapeutic effect than L-arginine due to its greater ability to increase nitric oxide production.
L-citrulline production from L-arginine by macrophage nitric oxide synthase. The ureido oxygen derives from dioxygen.
The study investigates the production of L-citrulline from L-arginine by macrophage nitric oxide synthase. It demonstrates that the ureido oxygen in L-citrulline derives from dioxygen rather than water, using gas chromatography/mass spectrometry analysis.