Change of some oxidative stress parameters after supplementation with whey protein isolate in patients with type 2 diabetes

Metabolic Syndrome and Biotherapeutic Activity of Dairy (Cow and Buffalo) Milk Proteins and Peptides: Fast Food-Induced Obesity Perspective-A Narrative Review

Metabolic syndrome (MS) is defined by the outcome of interconnected metabolic factors that directly increase the prevalence of obesity and other metabolic diseases. Currently, obesity is considered one of the most relevant topics of discussion because an epidemic heave of the incidence of obesity in both developing and underdeveloped countries has been reached. According to the World Obesity Atlas 2023 report, 38% of the world population are presently either obese or overweight. One of the causes of obesity is an imbalance of energy intake and energy expenditure, where nutritional imbalance due to consumption of high-calorie fast foods play a pivotal role. The dynamic interactions among different risk factors of obesity are highly complex; however, the underpinnings of hyperglycemia and dyslipidemia for obesity incidence are recognized. Fast foods, primarily composed of soluble carbohydrates, non-nutritive artificial sweeteners, saturated fats, and complexes of macronutrients (protein-carbohydrate, starch-lipid, starch-lipid-protein) provide high metabolic calories. Several experimental studies have pointed out that dairy proteins and peptides may modulate the activities of risk factors of obesity. To justify the results precisely, peptides from dairy milk proteins were synthesized under in vitro conditions and their contributions to biomarkers of obesity were assessed. Comprehensive information about the impact of proteins and peptides from dairy milks on fast food-induced obesity is presented in this narrative review article.

Whey protein supplementation reduced the liver damage scores of rats fed with a high fat-high fructose diet

Different functional foods with bioactive nutrients are being explored for the management of NAFLD. Whey proteins are rich in bioactive peptides and are suggested to show antioxidant and anti-inflammatory effects. We aim to test the hypothesis that the whey protein supplementation following a high fat-high fructose (HFHF) diet would protect against liver damage, inflammation, endotoxemia and steatosis in male Wistar rats. 36 rats were randomized into four groups for 8 weeks as the HFHF diet group, HFHF diet and whey protein isolate (WPI-200mg/kg/day) group (HFHF+WPI), control (C) group, and C+WPI (200mg/kg/day) group. Rats fed with a HFHF diet had higher final body weight compared to C and C+WPI groups (p = 0.002). Thus, WPI showed no significant effects for the body weight of rats with a HFHF diet. On the other hand, the HFHF+WPI group had significantly lower abdominal circumference when compared with the HFHF group (p<0,001). Higher serum CRP levels were observed in the groups with a HFHF diet (p<0,001) and WPI supplementation showed no effects on CRP levels. Whey protein supplementation resulted with lower total liver damage score in HFHF+WPI group compared with the HFHF diet group (p<0,001). Conversely, higher liver damage scores were observed with the C+WPI group compared to C group (p<0,001). HFHF diet resulted with higher expression of TLR-4 in the liver meanwhile WPI supplementation showed no effects on liver TLR-4 expression. We observed higher colon Occludin expression in HFHF+WPI and C+WPI groups compared with HFHF and C groups (p<0,001). Our results showed that, whey protein supplementation might help improve liver damage associated with a high fat-high fructose diet and increase the expression of Occludin in the small intestine and colon.

Potential of milk-derived bioactive peptides as antidiabetic, antihypertensive, and xanthine oxidase inhibitors: a comprehensive bibliometric analysis and updated review

Bioactive peptides consist of small protein fragments, which are inactive in their original conformation, and they become active when released from these through enzymatic hydrolysis or fermentation processes. The bioactivity of such peptides has been extensively reported in the literature as contributors to organic homeostasis processes, as well as in immunomodulation, organism defense against oxidative processes, among others. In this study, reports of the activity of BPs isolated from milk with the potential glycemic control, antihypertensive activity, and inhibitors of uric acid formation were compiled. A systematic literature review and bibliometric analysis were conducted, using the PICO strategy for the research. The temporal analysis of publications revealed a growing interest in the investigation of bioactive peptides with potential antidiabetic, antihypertensive, and xanthine oxidase inhibitory activities, using dairy sources as products for their extraction. The literature analysis also revealed an increase in research involving non-bovine dairy products for bioactive peptide extraction. The collaboration network among authors exhibited weaknesses in scientific cooperation. Regarding the analysis of keywords, the usage of terms such as "bioactive peptides", "antioxidant", "antihypertensive", and "diabetes" was evident, constituting the main research clusters. Peptides with low molecular weight, typically < 10 kDa, of hydrophobic nature with aliphatic and aromatic chains, have significant implications in molecular interactions for the required activities. Although there is a growing interest in the industry regarding the utilization of bioactive peptides as potential drugs, there is a need to address gaps related to elucidating their interactions with cellular targets and their use in human therapy.

Whey proteins as a functional food: Health effects, functional properties, and applications in food

Functional foods are defined as foods and ingredients that exhibit health benefits beyond their nutritional value. Research on functional foods is increasing rapidly as they may help prevent and manage some non-communicable diseases. Whey proteins are recognized as a high-quality nutrient source and known to contain some bioactive components. They are rich in essential amino acids such as cysteine, branched-chain amino acids such as leucine, valine, and isoleucine, and bioactive peptides. Whey proteins look promising as a potential functional food, given its antioxidant, anti-inflammatory, blood pressure lowering, anti-obesity, and appetite suppressing effects that is discussed in the literature. Whey proteins also show functional properties that play an essential role in food processing as an emulsifier, fat-replacer, gelling and encapsulating agent and are known to improve sensory and textural characteristics of food. This review focuses on the functional food aspects of whey proteins, associated health effects, and current food applications.

Effects of supplementation with milk protein on glycemic parameters: a GRADE-assessed systematic review and dose-response meta-analysis

BACKGROUND

It is suggested that supplementation with milk protein (MP) has the potential to ameliorate the glycemic profile; however, the exact impact and certainty of the findings have yet to be evaluated. This systematic review and dose-response meta-analysis of randomized controlled trials (RCTs) assessed the impact of MP supplementation on the glycemic parameters in adults.

METHODS

A systematic search was carried out among online databases to determine eligible RCTs published up to November 2022. A random-effects model was performed for the meta-analysis.

RESULTS

A total of 36 RCTs with 1851 participants were included in the pooled analysis. It was displayed that supplementation with MP effectively reduced levels of fasting blood glucose (FBG) (weighted mean difference (WMD): -1.83 mg/dL, 95% CI: -3.28, -0.38; P = 0.013), fasting insulin (WMD: -1.06 uU/mL, 95% CI: -1.76, -0.36; P = 0.003), and homeostasis model assessment of insulin resistance (HOMA-IR) (WMD: -0.27, 95% CI: -0.40, -0.14; P < 0.001) while making no remarkable changes in serum hemoglobin A1c (HbA1c) values (WMD: 0.01%, 95% CI: -0.14, 0.16; P = 0.891). However, there was a significant decline in serum levels of HbA1c among participants with normal baseline body mass index (BMI) based on sub-group analyses. In addition, HOMA-IR values were significantly lower in the MP supplement-treated group than their untreated counterparts in short- and long-term supplementation (≤ 8 and > 8 weeks) with high or moderate doses (≥ 60 or 30-60 g/d) of MP or whey protein (WP). Serum FBG levels were considerably reduced upon short-term administration of a low daily dose of WP (< 30 g). Furthermore, the levels of serum fasting insulin were remarkably decreased during long-term supplementation with high or moderate daily doses of WP.

CONCLUSION

The findings of this study suggest that supplementation with MP may improve glycemic control in adults by reducing the values of fasting insulin, FBG, and HOMA-IR. Additional trials with longer durations are required to confirm these findings.

Whey Protein Premeal Lowers Postprandial Glucose Concentrations in Adults Compared with Water-The Effect of Timing, Dose, and Metabolic Status: a Systematic Review and Meta-analysis

BACKGROUND

Serving whey protein before a meal in order to lower postprandial blood glucose concentrations is known as a premeal. The underlying mechanisms are only partly understood but may involve stimulation of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and insulin secretion together with a slower gastric emptying rate.

OBJECTIVES

The objective of this systematic review and meta-analysis was to review all randomized clinical trials investigating premeals with whey protein in comparison with a nonactive comparator (control) that evaluated plasma glucose, GLP-1, GIP, insulin, and/or gastric emptying rate. Secondary aims included subgroup analyses on the timing and dose of the premeal together with the metabolic state of the participants [lean, obese, and type 2 diabetes mellitus (T2DM)].

METHODS

We searched EMBASE, CENTRAL, PUBMED, and clinicaltrials.gov and found 16 randomized crossover trials with a total of 244 individuals. The last search was performed on 9 August, 2022.

RESULTS

Whey protein premeals lowered peak glucose concentration by -1.4 mmol/L [-1.9 mmol/L; -0.9 mmol/L], and the area under the curve for glucose was -0.9 standard deviation (SD) [-1.2 SD; -0.6 SD] compared with controls (high certainty). In association with these findings, whey protein premeals elevated GLP-1 (low certainty) and peak insulin (high certainty) concentrations and slowed gastric emptying rate (high certainty) compared with controls. Subgroup analyses showed a more pronounced and prolonged glucose-lowering effect in individuals with T2DM compared with participants without T2DM. The available evidence did not elucidate the role of GIP. The protein dose used varied between 4 and 55 g, and meta-regression analysis showed that the protein dose correlated with the glucose-lowering effects.

CONCLUSIONS

In conclusion, whey protein premeals lower postprandial blood glucose, reduce gastric emptying rate, and increase peak insulin. In addition, whey protein premeals may elevate plasma concentrations of GLP-1. Whey protein premeals may possess clinical potential, but the long-term effects await future clinical trials.

Effects of Whey Protein, Omega-3 Fatty Acid and Roux-En-Y Gastric Bypass on Body Weight, Biochemical Parameters and Organ Functions in an Obese Rat Model: Experimental Research

PURPOSE

Extreme obesity (EO) is one of the biggest public health problems in the world and has grown considerably over the years. The aim of the study is to examine the effect of Roux-en-Y gastric bypass (RYGB), whey protein (WP), and omega-3 polyunsaturated fatty acid (PUFA) supplementation applied to EO rats on weight loss, histopathological changes in internal organs and biochemical alterations.

MATERIALS AND METHODS

Wistar albino female rats (n = 28) were used in the study and randomly divided into four groups. All rats were made obese by adding high fructose corn syrup (HFCS) to their drinking water. After the EO, WP and omega-3 PUFA supplementation was given and RYGB process was applied. At the end of the study, glucose, total cholesterol, HDL, VLDL, AST, ALT and uric acid changes and liver, kidney and pancreatic tissues were evaluated histopathologically.

RESULTS

WP and omega-3 PUFA supplementation decreased body weight (p > 0.05). Omega-3 PUFA and RYGB caused a decrease in total cholesterol (p < 0.05), WP decreased HDL (p < 0.05), WP and omega-3 PUFA caused an increase in ALT (p < 0.05). WP has been shown to have greater curative effects in rat liver and kidney tissues. It has been determined that RYGB causes necrosis in the liver and HFCS causes inflammation in the kidney.

CONCLUSION

In the study; the positive effects of WP, omega-3 PUFA and bariatric surgery on obesity and dyslipidemia have been demonstrated. With this result, it was determined that WP, omega-3 PUFA supplementation and bariatric surgery were not superior to each other.

Effects of whey and soy protein supplementation on inflammatory cytokines in older adults: a systematic review and meta-analysis

BACKGROUND AND AIMS

Low-grade inflammation is a mediator of muscle proteostasis. This study aimed to investigate the effects of isolated whey and soy proteins on inflammatory markers.

METHODS

We conducted a systematic literature search of randomised controlled trials (RCT) through MEDLINE, Web of Science, Scopus and Cochrane Library databases from inception until September 2021. To determine the effectiveness of isolated proteins on circulating levels of C-reactive protein (CRP), IL-6 and TNF-α, a meta-analysis using a random-effects model was used to calculate the pooled effects (CRD42021252603).

RESULTS

Thirty-one RCT met the inclusion criteria and were included in the systematic review and meta-analysis. A significant reduction of circulating IL-6 levels following whey protein [Mean Difference (MD): -0·79, 95 % CI: -1·15, -0·42, I² = 96 %] and TNF-α levels following soy protein supplementation (MD: -0·16, 95 % CI: -0·26, -0·05, I² = 68 %) was observed. The addition of soy isoflavones exerted a further decline in circulating TNF-α levels (MD: -0·20, 95 % CI: -0·31, -0·08, I² = 34 %). According to subgroup analysis, whey protein led to a statistically significant decrease in circulating IL-6 levels in individuals with sarcopenia and pre-frailty (MD: -0·98, 95 % CI: -1·56, -0·39, I² = 0 %). These findings may be dependent on participant characteristics and treatment duration.

CONCLUSIONS

These data support that whey and soy protein supplementation elicit anti-inflammatory effects by reducing circulating IL-6 and TNF-α levels, respectively. This effect may be enhanced by soy isoflavones and may be more prominent in individuals with sarcopenia.

Early Detection Is the Best Prevention-Characterization of Oxidative Stress in Diabetes Mellitus and Its Consequences on the Cardiovascular System

Previous studies demonstrated an important role of oxidative stress in the pathogenesis of cardiovascular disease (CVD) in diabetic patients due to hyperglycemia. CVD remains the leading cause of premature death in the western world. Therefore, diabetes mellitus-associated oxidative stress and subsequent inflammation should be recognized at the earliest possible stage to start with the appropriate treatment before the onset of the cardiovascular sequelae such as arterial hypertension or coronary artery disease (CAD). The pathophysiology comprises increased reactive oxygen and nitrogen species (RONS) production by enzymatic and non-enzymatic sources, e.g., mitochondria, an uncoupled nitric oxide synthase, xanthine oxidase, and the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX). Considering that RONS originate from different cellular mechanisms in separate cellular compartments, adequate, sensitive, and compartment-specific methods for their quantification are crucial for early detection. In this review, we provide an overview of these methods with important information for early, appropriate, and effective treatment of these patients and their cardiovascular sequelae.

Effects of whey protein supplementation on adiposity, body weight, and glycemic parameters: A synthesis of evidence

AIMS

The aim of this review was to analyze the evidence of whey protein supplementation on body weight, fat mass, lean mass and glycemic parameters in subjects with overweight or type 2 diabetes mellitus (T2DM) undergoing calorie restriction or with ad libitum intake.

DATA SYNTHESIS

Overweight and obesity are considered risk factors for the development of chronic noncommunicable diseases such as T2DM. Calorie restriction is a dietary therapy that reduces weight and fat mass, promotes the improvement of glycemic parameters, and decreases muscle mass. The maintenance of muscle mass during weight loss is necessary in view of its implication in preventing chronic diseases and improving functional capacity and quality of life. The effects of increased protein consumption on attenuating muscle loss and reducing body fat during calorie restriction or ad libitum intake in overweight individuals are discussed. Some studies have demonstrated the positive effects of whey protein supplementation on improving satiety and postprandial glycemic control in short term; however, it remains unclear whether long-term whey protein supplementation can positively affect glycemic parameters.

CONCLUSIONS

Although whey protein is considered to have a high nutritional quality, its effects in the treatment of overweight, obese individuals and those with T2DM undergoing calorie restriction or ad libitum intake are still inconclusive.

Effects of Long-Term Supplementation of Bovine Colostrum on Iron Homeostasis, Oxidative Stress, and Inflammation in Female Athletes: A Placebo-Controlled Clinical Trial

Bovine colostrum supplementation has been suggested as a potential factor in reducing oxidative stress and inflammation. The primary objective of this study was to evaluate the effects of six months of bovine colostrum supplement intake (3.2 g; four capsules/day) in highly trained female athletes on changes in oxidative stress level, inflammation, and iron metabolism biomarkers after intense exercise. In this study, 20 trained female athletes were recruited. Participants were divided into two groups: 11 in the bovine colostrum (6-month supplementation) and 9 in the placebo group (6-month placebo supplementation). All participants completed an intense exercise test at the beginning of the experiment and after six months post-treatment. Blood samples were taken before, following exercise, and after 3 h recovery. Compared to the placebo group, the colostrum group showed a significant decrease in TBARS level (p< 0.01) at all time points, whereas a marked increase was observed in IL-6 (p < 0.01; pre-exercise) and SOD activity (p < 0.01), and transferrin (p < 0.01; rest period) and lactoferrin (p < 0.05; post-exercise) levels. The results suggested that 6-months of bovine colostrum supplementation is beneficial in the reduction of the harmful effects produced by free radicals (ROS), oxidative stress, and inflammation. In consequence, alleviation of the inflammatory response by bovine colostrum supplementation may also cause positive action on iron homeostasis in female athletes.

Whey protein protects liver mitochondrial function against oxidative stress in rats exposed to acrolein

Acrolein (AC) is one of the most toxic environmental pollutants, often associated with incomplete combustion of petrol, wood, and plastic, oil frying, and tobacco smoking, that causes oxidative damage to DNA and mitochondria. Considering that little is known about the protective effects of whey protein (WP) against AC-induced liver toxicity, the aim of our study was to learn more about them in respect to liver mitochondrial oxidative stress, respiratory enzymes, Krebs cycle enzymes, and adenosine triphosphate (ATP). To do that, we treated Sprague Dawley rats with daily doses of AC alone (5 mg/kg bw in 0.9 % NaCl solution), WP alone (200 mg/kg bw, in 0.9 % NaCl solution), or their combination by oral gavage for six days a week over 30 days. As expected, the AC group showed a drop in glutathione levels and antioxidant, transport chain, and tricarboxylic acid cycle enzyme activities and a significant rise in mitochondrial lipid peroxidation and protein carbonyl levels. Co-treatment with WP mitigated oxidative stress and improved enzyme activities. Judging by the measured parameters, WP reduced AC toxicity by improving bioenergetic mechanisms and eliminating oxidative stress.

A systematic review of whey protein supplementation effects on human glycemic control: A mechanistic insight

BACKGROUND/AIMS

Some studies showed that dietary factors such as whey protein (WP) are effective on glycemic regulation. Due to the current controversy about WP effects and mechanisms of its action on glycemic control, we conducted this systematic review to shed light on the subject.

METHODS

Web of Science, Medline (Pubmed), and Scopus online databases were searched from 2012 up to February 2022 using the following keywords: "whey protein" and "glycemic control"/"glycemia"/"glucose"/"insulin". The search included original English articles, human clinical trials with WP supplementation and measurement of glucose or insulin as an outcome, studies on healthy individuals/patients with diabetes mellitus (DM)/impaired fasting glucose (IFG).

RESULTS

Title/abstract of 1991 studies were reviewed. After excluding studies due to inappropriate full title and duplication, and exercising inclusion criteria, 58 studies were reviewed in detail. Ample evidence showed that WP decreased postprandial glucose incremental area under the curve (iAUC) and increased iAUCs of insulin and incretin hormones. WP affects glycemic control mainly through stimulating insulin and incretins secretion, slowing gastric emptying, and appetite suppression.

CONCLUSION

Although most of the recent evidence showed beneficial effects of WP supplementation on glycemic response, further long-term clinical trials are required which assess the long-term impact of WP supplementation and its exact mechanisms.

Effect of Lactoferrin Supplementation on Inflammation, Immune Function, and Prevention of Respiratory Tract Infections in Humans: A Systematic Review and Meta-analysis

Lactoferrin (Lf) is a glycoprotein present in human and bovine milk with antimicrobial and immune-modulating properties. This review aimed to examine the evidence for the effect of Lf supplementation on inflammation, immune function, and respiratory tract infections (RTIs) in humans. Online databases were searched up to December 2020 to identify relevant, English-language articles that examined the effect of Lf supplementation in human subjects of all ages, on either inflammation, immune cell populations or activity, or the incidence, duration, or severity of respiratory illness or RTIs. Twenty-five studies (n = 20 studies in adults) were included, of which 8 of 13 studies (61%) in adults reported a decrease in at least 1 systemic inflammatory biomarker. Immune function improved in 6 of 8 studies (75%) in adults, with changes in immune cell populations in 2 of 6 studies (33%), and changes in immune cell activity in 2 of 5 studies (40%). RTI outcomes were reduced in 6 of 10 studies (60%) (n = 5 in adults, n = 5 in children), with decreased incidence in 3 of 9 studies (33%), and either decreased frequency (2/4, 50%) or duration (3/6, 50%) in 50% of studies. In adults, Lf reduced IL-6 [mean difference (MD): -24.9 pg/mL; 95% CI: -41.64, -8.08 pg/mL], but not C-reactive protein (CRP) [standardized mean difference: -0.09; 95% CI: -0.82, 0.65], or NK cell cytotoxicity [MD: 4.84%; 95% CI: -3.93, 13.60%]. RTI incidence was reduced in infants and children (OR: 0.78; 95% CI: 0.61, 0.98) but not in adults (OR: 1.00; 95% CI: 0.76, 1.32). Clinical studies on Lf supplementation are limited, although findings show 200 mg Lf/d reduces systemic inflammation, while formulas containing 35-833 mg Lf/d may reduce RTI incidence in infants and children, suggesting improved immune function. Future research is required to determine optimal supplementation strategies and populations most likely to benefit from Lf supplementation. This trial was registered at PROSPERO (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021232186) as CRD42021232186.

Cysteine-Rich Whey Protein Isolate (CR-WPI) Ameliorates Erectile Dysfunction by Diminishing Oxidative Stress via DDAH/ADMA/NOS Pathway

Nitric oxide synthase- (NOS-) dependent endothelial dysfunction induced by oxidative stress (OS) is assumed to play a pivotal role in the pathogenesis and progression of diabetes mellitus-related erectile dysfunction (DMED). Cysteine-rich whey protein isolate (CR-WPI) is a widely used protein supplement and has been confirmed to reduce reactive oxygen species (ROS) by increasing cellular antioxidant glutathione (GSH). However, it is currently unknown whether CR-WPI elicits therapeutic effects in DMED. Here, we provide diabetic rats with CR-WPI to determine its effect on DMED and the underlying mechanisms. The results suggest that CR-WPI supplementation increased GSH biosynthesis and reduced ROS content and simultaneously upregulated the dimethylarginine dimethylaminohydrolase (DDAH)/asymmetrical dimethylarginine (ADMA)/nitric oxide synthase (NOS) metabolic pathway. Evaluation of intracavernous pressure (ICP) also showed an improvement of penile erectile function in CR-WPI-treated rats. The results of the vitro cell culture showed that glutathione pretreatment protected corpus cavernosum smooth muscle cells (CCSMC) from H₂O₂-induced apoptosis by decreasing Caspase 9 and Caspase 3 expressions. These results augur well for the potential therapeutic application of dietary CR-WPI supplementation for treating diabetic erectile dysfunction.

Effect of whey protein consumption on IL-6 and TNF-α: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

Due to inconsistent data about WP supplementation on inflammatory markers, present systematic review and meta-analysis was done to summarize its effect on TNF-α and IL-6.

METHODS

Our search was done in Pubmed, Scopus, Embase, and Cochrane up to June 2021. Weighted mean difference (WMD) and 95% confidence intervals (CI) was used to indicate the effect sizes. Conceivable sources of heterogeneity were detected by subgroup analysis.

RESULTS

Overall, 11 eligible RCTs were included. The pooled results showed that WP supplementation had no significant effect on TNF-α and IL-6 status compare to those receiving carbohydrate and other types of proteins as placebo. Results from subgroup analysis based on health status, study duration, WP dosage and sex, expressed no favorable effect of WP on TNF-α and IL-6 levels.

CONCLUSION

It can be concluded that whey supplementation had no favorable effects on inflammatory biomarkers including TNF- α and IL-6.

Hippocampus kuda protein hydrolysate improves male reproductive dysfunction in diabetic rats

The global prevalence of diabetes mellitus is rapidly increasing. This disease is associated with many complications including male reproductive dysfunctions and infertility. Seahorse ( Hippocampus kuda) is a marine teleost fish well known for its beneficial effects on the reproductive system in traditional Chinese medicine books. Recently, several studies have been shown that the enzymatic hydrolysate of seahorse has multiple pharmacological activities. This study aimed to investigate the seahorse peptide hydrolysate (SH) ameliorative effects on the diabetic-induced male reproductive dysfunction in rat models. The in vivo studies were carried out with three different doses of SH (4, 8, and 20 mg/kg) and the diabetes condition was induced by administrating with streptozotocin (35 mg/kg) and fed a 40% high-fat diet. Seahorse hydrolysate (20 mg/kg) inhibited lipid peroxidation, increased antioxidant enzyme activity, and restored seminiferous tubules morphology in testis. Moreover, it improved reproductive dysfunction by increasing the level of testosterone, follicle-stimulating hormone, luteinizing hormone, sperm count, and motility. According to these results, we suggested that SH exhibited amelioration effects on the reproductive dysfunction.

Phytochemical profile, antioxidant, α-amylase inhibition, binding interaction and docking studies of Justicia carnea bioactive compounds with α-amylase

The present study investigated the antioxidant and invitro antidiabetic capacities of Justicia carnea aqueous leaf extract (JCAE) using α-amylase inhibition model. α-Amylase binding-interaction with JCAE was also investigated using fluorescence spectroscopy and molecular docking. Phytochemical screening and Gas Chromatography-Mass Spectrometry (GC-MS) analysis indicated presence of bioactive compounds. Phenolic (132 mg GAE/g) and flavonoid contents (31.08 mg CE/g) were high. JCAE exhibited high antioxidant capacity and effectively inhibited α-amylase activity (IC50, 671.43 ± 1.88 μg/mL), though lesser than acarbose effect (IC50, 108.91 ± 0.61 μg/mL). α-Amylase intrinsic fluorescence was quenched in the presence of JCAE. Ultraviolet-visible and FT-IR spectroscopies affirmed mild changes in α-amylase conformation. Synchronous fluorescence analysis indicated alterations in the microenvironments of tryptophan residues near α-amylase active site. Molecular docking affirmed non-polar interactions of compounds 6 and 7 in JCAE with Asp-197 and Trp-58 residues of α-amylase, respectively. Overall, JCAE indicated potential to prevent postprandial hyperglycemia by slowing down carbohydrate hydrolysis.

Nutritional Effects of the Enteral Nutritional Formula on Regulation of Gut Microbiota and Metabolic Level in Type 2 Diabetes Mellitus Mice

PURPOSE

Due to the adverse effects of antidiabetic drugs, nowadays, nutraceuticals have been of much interest to investigators. Therefore, the present study aimed to explore the potential effects of enteral nutritional (EN) formulas on the gut microbiota and metabolic regulation of type 2 diabetes mellitus (T2DM) mice and compare the differences between whey protein and soy protein.

METHODS

EN formulas made of whey protein or soy protein were administered for five weeks and then mice tissue samples were obtained to examine the metabolic parameters and histopathology of the pancreas, liver, jejunum and colon. 16S rRNA V3-V4 region gene sequencing was used to analyze the changes in the gut microbiota.

RESULTS

After the five-week intervention, the alpha diversity had recovered slightly, and the soy protein group (SPG) achieved a better effect than the whey protein group (LPG). The overall composition of gut microbiota was regulated. The abundance of Bacteroidetes and TM7 had raised significantly and the abundance of Firmicutes and Deferribacteres had declined after treatment, with no significant difference between the LPG and SPG. The types of beneficial bacteria were increased at the genus and species level. The level of hexokinase (HK) and pyruvate kinase (PK) had significantly recovered and inhibited the level of α-glucosidase. In addition, the EN formulas treatment reduced the levels of inflammatory factor (TNF-α) in liver and muscle. The level of glucose transporter type 2 (GLUT-2) levels in the liver and intestine also significantly increased. Moreover, the metabolism regulation of the SPG was better than that of the LPG. The EN formulas treatment improved the pancreas, liver, jejunum and colon histology.

CONCLUSION

The EN formulas regulated the overall structure of the gut microbiota and improved the metabolic level in streptozotocin/high-fat diet (STZ/HFD) diabetic mice. Therefore, EN formula may potentially become an effective nutritional adjunctive therapy for T2DM.