In ovo feeding of creatine monohydrate increases performances of hatching and development in breeder chicks

The current investigation was conducted to test the potential effects of in ovo feeding of creatine monohydrate (CMH) on hatchability, embryonic mortality, hatching weight, and development of heart and gastrointestinal tract (main organs and regions) of breeder chick embryos. Rhode Island Red fertile eggs were randomly distributed into seven experimental treatments: untreated egg (control), a sterile buffered solution (0.50% NaCl), and five solutions containing increased levels of CMH (0.50, 1.00, 1.50, and 2.00%) + 0.50% NaCl, being separated in four groups/replicates (three with 15 eggs and one with 16 eggs), totaling 61 eggs/treatment and a total of 427 fertile eggs used. All-in ovo injected groups with CMH decreased the hatchability and increased the intermediary embryonic mortality. At hatching, all-in ovo injected groups with CMH also increased the hatching weight and stimulated the development of the heart and the total length of the gastrointestinal tract, especially important organs for digestion of nutrients (yolk sac, pro-ventricle and gizzard) and regions for nutrient absorption (jejunum + ileum and colon + rectum). Conclusively, the in ovo feeding using CMH showed positive impacts on hatching weight and the development of gastrointestinal tract of chicks. However, caused negative impacts on hatchability.

Pilot study protocol of a randomized controlled trial for the potential effects of creatine monohydrate on persistent post-concussive symptoms

Background

Mild traumatic brain injury or concussion is a global public concern, with an estimated annual incidence between 48 million and 96 million worldwide. It is a socioeconomical problem, and almost one-third of individuals with concussion suffer from severe persistent post-concussive symptoms (PPCS), with an increased risk of unemployment or terminating their studies. To date, no single treatment is available with guaranteed success. Creatine monohydrate (CrM) has shown potential as a treatment for post-concussive symptoms, having a positive impact on cognitive function, chronic fatigue, depression, and anxiety. The aim of this study is to examine the effect of CrM on PPCS assessed using the Rivermead Post-Concussion Symptoms Questionnaire (RPQ).

Methods

The study is designed as a double-blinded randomised controlled trial. Study participants are found through neurological outpatient clinics in Denmark or through social media. They will be between 25 and 35 years of age, will have suffered from PPCS for 6-12 months prior to inclusion, and will have no comorbidities. The participants will be randomly allocated to either an intervention group (INT), placebo group (PLA), or control group (CG). Baseline data will be collected immediately after inclusion, and the study period will be 7 weeks. Follow-up data will be collected 1 week after the end of the study period. The primary outcome of the study is changes in RPQ score. Changes in weight and training status will be adjusted for as potential confounders.

Ethics and dissemination

This protocol is approved by the National Committee on Health Research (97508) and by the Danish Data Protection Agency 11.651. The investigators intend to submit their study findings for publication in peer-reviewed journals and disseminate the findings via presentation at academic meetings/conferences.Clinical Trial registration: NCT05562232, registered September 30, 2022.

Effects of creatine supplementation on memory in healthy individuals: a systematic review and meta-analysis of randomized controlled trials

CONTEXT

From an energy perspective, the brain is very metabolically demanding. It is well documented that creatine plays a key role in brain bioenergetics. There is some evidence that creatine supplementation can augment brain creatine stores, which could increase memory.

OBJECTIVE

A systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to determine the effects of creatine supplementation on memory performance in healthy humans.

DATA SOURCES

The literature was searched through the PubMed, Web of Science, Cochrane Library, and Scopus databases from inception until September 2021.

DATA EXTRACTION

Twenty-three eligible RCTs were initially identified. Ten RCTs examining the effect of creatine supplementation compared with placebo on measures of memory in healthy individuals met the inclusion criteria for systematic review, 8 of which were included in the meta-analysis.

DATA ANALYSIS

Overall, creatine supplementation improved measures of memory compared with placebo (standard mean difference [SMD] = 0.29, 95%CI, 0.04-0.53; I2 = 66%; P = 0.02). Subgroup analyses revealed a significant improvement in memory in older adults (66-76 years) (SMD = 0.88; 95%CI, 0.22-1.55; I2 = 83%; P = 0.009) compared with their younger counterparts (11-31 years) (SMD = 0.03; 95%CI, -0.14 to 0.20; I2 = 0%; P = 0.72). Creatine dose (≈ 2.2-20 g/d), duration of intervention (5 days to 24 weeks), sex, or geographical origin did not influence the findings.

CONCLUSION

Creatine supplementation enhanced measures of memory performance in healthy individuals, especially in older adults (66-76 years).

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. 42021281027.

Effect of in ovo creatine monohydrate on hatchability, post-hatch performance, breast muscle yield and fiber size in chicks from young breeder flocks

Younger broiler breeder flocks produce smaller eggs containing smaller yolks, with potentially lower energy reserves for the developing chick. Creatine is a naturally occurring energy source and is abundant in metabolically active tissues; providing this to chicks in ovo should provide additional energy to improve hatchability and post-hatch growth. Thus, post-hatch performance of male and female chicks hatched from younger breeder flocks supplemented with creatine monohydrate (CrM) in ovo was investigated. Four hundred eggs from Ross 308 breeder hens aged 27 to 29 wk were collected and at d 14 assigned to a treatment group and received 1) no injection, 2) 0.75% saline injection, or 3) 8.16 mg creatine monohydrate in 0.75% saline. At hatch 72 birds (24/treatment) were euthanized and BW, breast muscle, heart and liver weight were obtained, and breast muscle tissue was placed in 10% buffered formalin. Birds were then placed in raised metal pens (24 pens; 10-11 birds/pen; 8 replicates/treatment) and grown to d 42 with BW and pen feed intake measured once a week. At d 42, ninty-six birds were euthanized (2 male and 2 female/pen) and the process occurred as at hatch. Body composition was obtained for 48 birds (2/pen; 1 male,1 female) with a dual energy X-ray absorptiometry (DXA) scanner. Breast muscle tissue was processed for histological analysis and breast muscle fiber parameters were analyzed by ImageJ. While not statistically significant, the CrM treatment group saw an improved hatch rate (CrM: 93.5%, Saline: 88.6%, Control: 88.8%) and reduced early post hatch mortality. Chicks given in ovo CrM had significantly increased creatine concentrations in both liver and heart tissue at hatch compared to those in the saline and control groups. BW, BW gain, and final body composition parameters were not statistically different between treatments and in ovo CrM did not affect breast muscle fiber number or area. The creatine injection likely improved the energy status of the growing embryo resulting in the improved hatch rate but leaving little reserves for post-hatch growth.

Effect of creatine supplementation on kidney stones recurrence in an athlete: a case report

INTRODUCTION

Several studies examined the effects of creatine monohydrate supplementation on renal function, but no previous study has investigated its effects on kidney stones in humans.

OBSERVATION

A renal ultrasound in a healthy young athlete (without a known renal morphological anomaly, normal kidney function, normal phospholipid and uric acid data) revealed a kidney stone of 11 mm in the lower right calyx. Extracorporeal shock wave lithotripsy was applied in order to break the down stone. Twentyone days later, a follow-up renal ultrasound showed the absence of stones in the kidney. One week later, the athlete started creatine monohydrate supplementation for two months. Fourteen months after stopping creatine monohydrate supplementation, a third renal ultrasound confirmed the absence of stones in the kidney.

CONCLUSION

Two months of creatine monohydrate supplementation in an athlete with a history of kidney stones could not be associated with kidney stone recurrence in the long run.

Associations between Adverse Childhood Experiences and Performance-Enhancing Substance Use among Young Adults

BACKGROUND AND OBJECTIVE

Adverse childhood experiences (ACEs) are associated with negative health outcomes, yet their associations with performance-enhancing substance (PES) use are unclear. This study aimed to determine whether ACEs predict greater use of legal and illegal PES in young adults.

METHODS

We analyzed data from the National Longitudinal Study of Adolescent to Adult Health (n = 14,322), Waves I (1994-1995) and III (2001-2002). ACEs included childhood sexual abuse, physical abuse, two neglect indicators, and cumulative ACEs. Legal (e.g. creatine monohydrate) and illegal (e.g. non-prescription anabolic-androgenic steroids; AAS) PES use was assessed.

RESULTS

Sexual abuse had the greatest effect and predicted higher odds of legal PES use (men: adjusted odds ratio [AOR] 1.66, 95% confidence interval [CI] 1.06-2.59; women: AOR 3.74, 95% CI 1.63-8.59) and AAS use (men: AOR 8.89, 95% CI 5.37-14.72; women: AOR 5.73, 95% CI 2.31-14.18). Among men, a history of physical abuse (AOR 3.04, 95% CI 2.05-4.52), being left alone by a parent/guardian (AOR 2.33, 95% CI 1.50-3.60), and basic needs not being met (AOR 3.47, 95% CI 2.30-5.23) predicted higher odds of AAS use. Among women, basic needs not being met (AOR 2.94, 95% CI 1.43-6.04) predicted higher odds of AAS use. Among both men and women, greater number of cumulative ACEs predicted higher odds of both legal and illegal PES use.

CONCLUSIONS

ACEs predict greater PES use among young adults. Clinicians should monitor for PES use among those who have experienced ACEs and provide psychoeducation on the adverse effects associated with PES use.

Risk of Adverse Outcomes in Females Taking Oral Creatine Monohydrate: A Systematic Review and Meta-Analysis

Creatine Monohydrate (CrM) is a dietary supplement routinely used as an ergogenic aid for sport and training, and as a potential therapeutic aid to augment different disease processes. Despite its increased use in recent years, studies reporting potential adverse outcomes of CrM have been mostly derived from male or mixed sex populations. A systematic search was conducted, which included female participants on CrM, where adverse outcomes were reported, with meta-analysis performed where appropriate. Six hundred and fifty-six studies were identified where creatine supplementation was the primary intervention; fifty-eight were female only studies (9%). Twenty-nine studies monitored for adverse outcomes, with 951 participants. There were no deaths or serious adverse outcomes reported. There were no significant differences in total adverse events, (risk ratio (RR) 1.24 (95% CI 0.51, 2.98)), gastrointestinal events, (RR 1.09 (95% CI 0.53, 2.24)), or weight gain, (mean difference (MD) 1.24 kg pre-intervention, (95% CI -0.34, 2.82)) to 1.37 kg post-intervention (95% CI -0.50, 3.23)), in CrM supplemented females, when stratified by dosing regimen and subject to meta-analysis. No statistically significant difference was reported in measures of renal or hepatic function. In conclusion, mortality and serious adverse events are not associated with CrM supplementation in females. Nor does the use of creatine supplementation increase the risk of total adverse outcomes, weight gain or renal and hepatic complications in females. However, all future studies of creatine supplementation in females should consider surveillance and comprehensive reporting of adverse outcomes to better inform participants and health professionals involved in future trials.

Searching for a better formulation to enhance muscle bioenergetics: A randomized controlled trial of creatine nitrate plus creatinine vs. creatine nitrate vs. creatine monohydrate in healthy men

A novel creatine blend (creatine nitrate mixed with creatinine, CN-CRN) has been anecdotally suggested to be superior to traditional creatine formulations for bioavailability and performance. However, does CN-CRN supremely affects creatine levels in the blood and skeletal muscle of healthy humans remain currently unknown. This randomized, controlled, double-blind, crossover trial evaluated the acute effects of single-dose CN-CRN on serum creatine levels, and 5-days intervention with CN-CRN on skeletal muscle creatine and safety biomarkers in healthy men. Ten healthy young men (23.6 ± 2.9 years) were allocated to receive either CN-CRN (3 grams of creatine nitrate mixed with 3 grams of creatinine), pure creatine nitrate (3 grams, CN), or regular creatine monohydrate (3 grams, CRM) by oral administration. We found that CN-CRN resulted in a more powerful rise in serum creatine levels comparing to either CN or CRM after a single-dose intervention, as evaluated with the area under the concentration-time curve calculation (701.1 ± 62.1 (µmol/L) × min versus 622.7 ± 62.9 (µmol/L) × min versus 466.3 ± 47.9 (µmol/L) × min; p < .001). The peak serum creatine levels at 60-min sampling interval were significantly higher in CN-CRN group (183.7 ± 15.5 µmol/L), as compared to CN group (163.8 ± 12.9 µmol/L) and CRM group (118.6 ± 12.9 µmol/L) (p < .001). This was accompanied by a significantly superior increase in muscle creatine levels after CN-CRN administration at 5-days follow-up, as compared to CN and CRM, respectively (9.6% versus 8.0% versus 2.1%; p = .01). While 2 out of 10 participants were found to be nonresponsive to CN intervention (20.0%) (e.g., no amplification in muscle creatine levels found at 5-days follow-up), and 3 participants out of 10 were nonresponsive in CRM trial (30%), no nonresponders were found after CN-CRN administration, with individual upswing in total muscle creatine varied in this group from 2.0% (lowest increment) to 16.8% (highest increment). Supplemental CN-CRN significantly decreased estimated glomerular filtration rate (eGFR) at 5-days follow-up, as compared to other interventions (p = .004), with the average reduction was 14.8 ± 7.7% (95% confidence interval; from 9.3 to 20.3). Nevertheless, no single participant experienced a clinically relevant reduction in eGFR (< 60 ml/min/1.73 m2) throughout the course of the trial. Liver enzymes remained in reference ranges throughout the study, with no participant experienced high liver blood tests (e.g., AST > 40 units per L or ALT >56 units per L). Besides, no participant reported any major side effects during the trial, while the odors of CN-CRN and CN formulations were considered somewhat unpleasant in 8 out of 10 participants (80.0%). Our results suggest that CN-CRN is a preferred and relatively safe alternative to traditional creatine formulations for improved creatine bioavailability in the blood and skeletal muscle after single-dose and 5-days interventions.

Creatine Monohydrate and Guanidinoacetic Acid Supplementation Affects the Growth Performance, Meat Quality, and Creatine Metabolism of Finishing Pigs

This study aimed to investigate the effects of creatine monohydrate (CMH) and guanidinoacetic acid (GAA) supplementation on the growth performance, meat quality, and creatine metabolism of finishing pigs. The pigs were randomly allocated to three treatment groups: the control group, CMH group, and GAA group. In comparison to the control group, CMH treatment increased average daily feed intake and GAA treatment increased average daily feed intake and average daily gain of pigs. In addition, CMH and GAA treatment increased pH_45 min, myofibrillar protein solubility, and calpain 1 mRNA expression level and decreased the drip loss and shear force value in longissimus dorsi or semitendinosus muscle. Moreover, CMH and GAA supplementation increased the concentrations of creatine and phosphocreatine and the mRNA expressions of guanidinoacetate N-methyltransferase and creatine transporter in longissimus dorsi muscle, semitendinosus muscle, liver, or kidneys and decreased the mRNA expressions of arginine:glycine amidinotransferase in kidneys. In conclusion, CMH and GAA supplementation could improve the growth performance and meat quality and alter creatine metabolism of finishing pigs.

Absolute Oral Bioavailability of Creatine Monohydrate in Rats: Debunking a Myth

Creatine is an ergogenic compound used by athletes to enhance performance. Supplementation with creatine monohydrate (CM) has been suggested for musculoskeletal and neurological disorders. Until now, little is known about its pharmacokinetic profile. Our objective was to determine the oral bioavailability of CM and the influence of dose on oral absorption. Rats were dosed orally with low dose (10 mg/kg) or high dose (70 mg/kg) 13C-labeled CM. Blood samples were removed at various time points. Muscle and brain tissue were collected at the conclusion of the study. Plasma and tissue levels of 13C-labeled creatine were determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Physiologically based pharmacokinetic (PBPK) models of CM were built using GastroPlus™. These models were used to predict the plasma concentration-time profiles of creatine hydrochloride (CHCL), which has improved aqueous solubility compared to CM. Absolute oral bioavailability for low dose CM was 53% while high dose CM was only 16%. The simulated Cmax of 70 mg/kg CHCL was around 35 μg/mL compared to 14 μg/mL for CM with a predicted oral bioavailability of 66% with CHCL compared to 17% with CM. Our results suggest that the oral bioavailability of CM is less than complete and subject to dose and that further examination of improved dosage formulations of creatine is warranted.

Creatine Monohydrate Enhances Energy Status and Reduces Glycolysis via Inhibition of AMPK Pathway in Pectoralis Major Muscle of Transport-Stressed Broilers

Creatine monohydrate (CMH) contributes to reduce transport-induced muscle rapid glycolysis and improve meat quality of broilers, but the underlying mechanism is still unknown. Therefore, this study aimed to investigate the molecular mechanisms underlying the ameliorative effects of CMH on muscle glycolysis metabolism of transported broilers during summer. The results showed that 3 h transport during summer elevated chicken live weight loss and plasma corticosterone concentration; decreased muscle concentrations of ATP, creatine, and energy charge value; increased muscle AMP concentration and AMP/ATP ratio; and upregulated muscle mRNA expression of LKB1 and AMPKα2, as well as protein expression of p-LKB1^Thr189 and p-AMPKα^Thr172, which subsequently resulted in rapid glycolysis in the pectoralis major muscle and consequent reduction of meat quality. Dietary addition of CMH at 1200 mg/kg ameliorated transport-induced rapid muscle glycolysis and reduction of meat quality via enhancement of the energy-buffering capacity of intramuscular phosphocreatine/creatine system and inhibition of AMPK pathway.

Effect of creatine monohydrate supplementation on learning, memory and neuromuscular coordination in female albino mice

BACKGROUND

Research findings made over the last few years have highlighted the important role of creatine (Cr) in health and disease. However, limited information is available regarding the effect of Cr supplementation on cognation. Present study was designed to determine the effect of variable doses of Cr (1% and 3%) on selected parameters of female albino mice behaviour.

METHODS

Following weaning, on 20th postnatal day, female albino mice were divided into three groups on the basis of dietary supplementation. Control group were was fed with normal rodent diet, whereas treated groups received diet supplemented with 1% and 3% Creatine monohydrate (Ssniff, Germany) for 10 weeks. Morris water maze (MWM), Rota rod and open field (OF) tests were carried out at the end of diet supplementation for neurofunctional assessment in all the groups.

RESULTS

Data analysis showed that Cr supplementation did not affect the muscular activity and during rota rod test as well as locomotor and exploratory behaviour during OF test. Results of MWM probe trial indicated that mice supplemented with 3% Cr had significantly more entries in platform area than other two treatments (p=0.03) indicating improved spatial memory. Body weight remained unaffected (p>0.05) when compared between three experimental treatments.

CONCLUSION

Female mice supplemented with 3% Cr showed improved spatial memory than mice fed on 1% Cr-supplemented diet and mice on normal rodent diet.

Effects of a High Protein and Omega-3-Enriched Diet with or Without Creatine Supplementation on Markers of Soreness and Inflammation During 5 Consecutive Days of High Volume Resistance Exercise in Females

We examined if two different dietary interventions affected markers of soreness and inflammation over a 5-day high-volume resistance training protocol in females that resistance-trained 8 weeks prior. Twenty-eight females (age: 20 ± 1 yr; body mass: 63.5 ± 1.6 kg, height: 1.67 ± 0.01 m) completed 4 weeks of pre-training (weeks 1-4) followed by a subsequent 4-week training period along with a dietary intervention (weeks 5-8). Dietary interventions from weeks 5-8 included: a) no intervention (CTL, n = 10) b) a higher-protein diet supplemented with hydrolyzed whey protein (50 g/d) and omega-3 fatty acids (900 mg/d) (DI, n = 8), and c) the DI condition as well as creatine monohydrate (5 g/d) (DI+C, n = 10). During week 9, participants resistance-trained for five consecutive days whereby 8 sets of 10 target repetitions at 70% one repetition maximum (1RM) were performed each day for bench press, back squat, deadlift, and hip-thrusters with the intent of eliciting muscle soreness and inflammation. Prior to and 24 h following each of the 5 bouts muscle soreness (DOMS) was assessed via questionnaire, and fasting blood was obtained and analyzed for serum cortisol, interleukin-6 (IL-6) and C-reactive protein (CRP). No group*time (G*T) or time effects were observed for training volume over the 5-d overreaching protocol. Furthermore, no group*time (G*T) or time effects were observed for serum cortisol, IL-6 or CRP, and DOMS actually decreased in all groups 24 h following the fifth day training bout. This study demonstrates that, regardless of protein, omega-3 fatty acid and/or creatine supplementation, 5 days of consecutive resistance training does not alter perceived muscle soreness, training volume, and/or markers of inflammation in novice resistance-trained females.

The Effects of Creatine Monohydrate on Permeability of Coronary Artery Endothelium and Level of Blood Lipoprotein in Diabetic Rats

BACKGROUND

Creatine monohydrate has beneficial effects on serum glucose. This study aimed to investigate the effects of creatine on serum biochemical markers and permeability of coronary arteries among diabetic rats.

MATERIAL AND METHODS

32 Wistar rats, which weighed 150-200 grams were randomly divided into 4 groups including: group I, control; group II, creatine monohydrate; group III, diabetic rats; and group IV, diabetic rats + creatine. Creatine monohydrate was applied by 400 mg/kg/daily for 5 months. Animals' weights and blood samples were taken before and after the study. Endothelial permeability rate was measured by Evans Blue method. Data were analysed by SPSS 16.

RESULTS

At the end of fifth month, rats' weights in diabetic group under treatment with creatine, compared to those without, increased significantly (p<0.0001). Also, the serum levels of triglyceride (TG), cholesterol, glucose and low density lipoprotein (LDL)- cholesterol decreased significantly among those under treatment with creatine (p<0.05), but high density lipoprotein (HDL)- cholesterol increased significantly (p<0.002). Permeability rate of coronary arteries was reduced significantly in the diabetic group treated by creatine compared to untreated groups, closed to the intact group (p<0.001).

CONCLUSION

Results of this study showed that creatine monohydrate caused an improvement of serum biochemical markers associated with diabetes and reduced the permeability rate of coronary arteries among diabetic rats.

Effects of creatine monohydrate supplementation on exercise-induced apoptosis in athletes: A randomized, double-blind, and placebo-controlled study

Background:

Creatine monohydrate (CrM) has been shown to be beneficial to health due to its antioxidant potential. Strenuous exercise is associated with oxidative stress, which could lead to apoptosis. We investigated the ability of CrM in amelioration of apoptosis induced by incremental aerobic exercise (AE) to exhaustion in young athletes.

Materials and Methods:

In a placebo-controlled, double-blind, randomized, parallel study, 31 young athletes (age 19.52 ± 2.75 years, body mass 79.24 ± 16.13 kg, height 1.73 ± 6.49 m, body fat 16.37% ± 5.92%) were randomly assigned to CrM (4 × 5 g/day, n = 15) or placebo (PL: 4 × 5 g/day of maltodextrine powder; n = 16) to investigate the effect of 7 days CrM on serum p53 and insulin-like growth factor-1 (IGF-1) concentration after acute incremental AE test to exhaustion. Subjects performed AE before (test 1) and after 7 days of supplementation (test 2).

Results:

Before supplementation, AE to exhaustion induced a significant increase in serum p53 and IGF-1 concentrations at both CrM and PL groups (P < 0.05). After supplementation, serum p53 concentrations were significantly lower in CrM than PL at post-AE (P < 0.05). There were no differences in IGF-1 concentrations between CrM and PL groups at post-AE (P > 0.05).

Conclusion:

Our results suggest that supplementation with CrM prevents apoptosis, as measured by decreases in p53 concentration, induced by AE to exhaustion in young athletes. However, CrM had no effect on IGF-1 concentration after AE to exhaustion in young athletes.

Effect of dietary creatine monohydrate supplementation on muscle lipid peroxidation and antioxidant capacity of transported broilers in summer

This experiment was to evaluate the effect of dietary supplementation with creatine monohydrate (CMH) during the finishing period on the muscle lipid peroxidation and antioxidant capacity of broilers that experienced transport stress in summer. A total of 320 male Arbor Acres broilers (28 d in age) were randomly allotted to 3 dietary treatments including a basal control diet without additional CMH (160 birds), or with 600 (80 birds) or 1,200 mg/kg (80 birds) CMH for 14 d. On the morning of d 42, after an 8-h fast, the birds fed the basal diets were divided into 2 equal groups, and all birds in the 4 groups of 80 birds were transported according to the following protocols: 1) a 0.75-h transport of birds on basal diets (as a lower-stress control group), 2) a 3-h transport of birds on basal diets, 3) a 3-h transport of birds on 600 or 4) 1,200 mg/kg CMH supplementation diets. The results showed that the 3-h transport decreased the concentration of creatine (Cr) in both the pectoralis major (PM) and the tibialis anterior (TA) muscles, increased the concentration of phosphocreatine (PCr) and PCr/Cr ratio in PM muscle, and elevated the concentrations of thiobarbituric acid-reactive substances and the activities of total superoxide dismutase and glutathione peroxidase in both the PM and TA muscles of birds (P < 0.05). In addition, transport also upregulated mRNA expression of avian uncoupling protein and heat shock protein 70 in both the PM and TA muscles, as well as avian peroxisome proliferator-activated receptor γ coactivator-1α in the TA muscle (P < 0.05). Dietary supplementation with 1,200 mg/kg CMH increased the concentrations of Cr and PCr in PM muscle, and Cr in TA muscle than those in the 3-h transport group (P < 0.05). However, contrary to our hypothesis, dietary CMH did not alter the measured parameters in relation to muscle lipid peroxidation and antioxidant capacity affected by 3-h transport (P > 0.05). These results indicate that dietary CMH supplementation does not provide any significant protection via directly scavenging free radicals or increased antioxidant capacity of transported broilers.

Effect of free creatine therapy on cisplatin-induced renal damage

Abstract Cisplatin is one of the commonly used anticancer drugs and nephrotoxicity limits its use. The aim of this study is to investigate the possible protective effect of creatine supplementation on cisplatin-induced nephrotoxicity. Sixty male Sprague-Dawley rats were divided into three groups: Group I: Cisplatin (n=20) (7 mg/kg cisplatin intraperitoneal (i.p.) single dose), group II: Cisplatin+creatine monohydrate (n=20) (7 mg/kg cisplatin i.p. single dose and 300 mg/kg creatine p.o. daily for 30 days starting on first day of cisplatin injection), group III: Control group (n=20) (Serum physiologic, 2.5 mL/kg i.p.). Sacrifications were performed at first week and 30th day. Blood urea nitrogen (BUN) and serum creatinine levels, histopathological evaluation, mitochondrial deoxyribonucleic acid (mtDNA) common deletion rates, and body weights of rats were evaluated. A significant decrease in body weight, higher values of kidney function tests, histopathological scores, and mtDNA deletion ratios were observed in group I compared to control group at days 7 and 30 (p<0.05). In group II, there was a slight decrease in body weight at same days (p=0.931 and 0.084, respectively). Kidney function tests, histopathological scores, and mtDNA common deletion ratios were statistically better in group II than group I at 7th and 30th day (p<0.05). Although creatine significantly reversed kidney functions and pathological findings, this improvement was not sufficient to reach normal control group's results at days 7 and 30. In conclusion, the present study demonstrates that creatine administration is a promising adjuvant protective drug for reducing nephrotoxic effect of cisplatin.

The effects of the recommended dose of creatine monohydrate on kidney function

We report a case of a heretofore healthy 18-year-old man who presented with a 2-day history of nausea, vomiting and stomach ache while taking creatine monohydrate for bodybuilding purposes. The patient had acute renal failure, and a renal biopsy was performed to determine the cause of increased creatinine and proteinuria. The biopsy showed acute tubular necrosis. In the literature, creatine monohydrate supplementation and acute tubular necrosis coexistence had not been reported previously. Twenty-five days after stopping the creatine supplements, the patient recovered fully. Even recommended doses of creatine monohydrate supplementation may cause kidney damage; therefore, anybody using this supplement should be warned about this possible side effect, and their renal functions should be monitored regularly.

Effects of beta-alanine on muscle carnosine and exercise performance: a review of the current literature

Muscle carnosine has been reported to serve as a physiological buffer, possess antioxidant properties, influence enzyme regulation, and affect sarcoplasmic reticulum calcium regulation. Beta-alanine (β-ALA) is a non-essential amino acid. β-ALA supplementation (e.g., 2-6 grams/day) has been shown to increase carnosine concentrations in skeletal muscle by 20-80%. Several studies have reported that β-ALA supplementation can increase high-intensity intermittent exercise performance and/or training adaptations. Although the specific mechanism remains to be determined, the ergogenicity of β-ALA has been most commonly attributed to an increased muscle buffering capacity. More recently, researchers have investigated the effects of co-ingesting β-ALA with creatine monohydrate to determine whether there may be synergistic and/or additive benefits. This paper overviews the theoretical rationale and potential ergogenic value of β-ALA supplementation with or without creatine as well as provides future research recommendations.

Evaluation of the stability of creatine in solution prepared from effervescent creatine formulations

The objectives of this study were to determine the cause of the crystallization in a large volume creatine supplement solution made from effervescent powders containing di-creatine citrate, and to characterize these crystals using thermal analyses and x-ray diffractometry. Creatine effervescent powders were dissolved in deionized water (pH 6.2) and stored both at room temperature (RT) (25 degrees C) and refrigerated condition (4 degrees C) over a period of 45 days. Creatine concentration was determined using high-performance liquid chromatography (HPLC). Intrinsic dissolution and saturated solubility of creatine, creatine monohydrate, and di-creatine citrate in water were determined and compared. Crystal growth was detected only in the refrigerated samples on the seventh day of storage. Differential Scanning Calorimetry (DSC) and x-ray diffraction (XRD) studies revealed that the crystals formed were of creatine monohydrate. Ninety percent creatine degradation was observed within 45 days for RT samples. However, at refrigerated condition this degradation was 80% within the same time period. The pH of the RT samples also increased from 3.6 to 4.5 during storage. No such increase was observed in the case of refrigerated samples. The intrinsic dissolution rate constants of the compounds decreased in the following order: di-creatine citrate > creatine > creatine monohydrate. In conclusion, di-creatine citrate used in effervescent formulation dissociates to creatine in aqueous solution and eventually crystallizes out as creatine monohydrate. Significant decrease in solubility and effect of pH contribute to this crystallization process.