Low Protein Diet Research Articles

Effects of Low Protein Diet on Body Weight and Hematological Parameters in Rats

Malnutrition is a condition in which the body is deficient or excessive in macronutrients and micronutrients such as carbohydrates, fats, proteins and vitamins. Malnutrition causes changes in body weight and blood tissue that inhibit the development of hematopoietic cells, resulting in anemia, leukopenia and bone marrow hypoplasia. This study aimed to examine the effect of feeding a diet with a protein level of 12% and 20 % for 6-week to Wistar rats. The parameters seen are the impact on body weight and selected hematological parameters included white blood cell, monocyte, lymphocyte, granulocyte, hemoglobin and mean corpuscular volume. This study found that rats fed with 12% protein showed significant differences in body weight and several hematological parameters such as monocytes, lymphocytes, hemoglobin and mean corpuscular volume compared to normal.

Engineered Carbon Nanocatalysts for Homocysteine Catabolism

Cystathionine-β-synthase (CBS) deficiency or homocystinuria (HCU) is a rare inherited disorder with main clinical features of osteoporosis, dislocation of the optic lenses, learning difficulties and thromboembolism. CBS is a key enzyme in methionine catabolism pathway. CBS deficiency impairs the conversion of homocysteine (Hcy) to cystathionine, which leads to extracellular buildup of Hcy in toxic concentrations. Patients with CBS deficiency have elevated plasma Hcy and methionine.Currently, there is no FDA approved drug for CBS deficiency. Clinical treatment options are low-protein diet and betaine for severely affected patients, and vitamin supplementation for mildly affected adults. Artificial protein-based enzymes for Hcy treatment are in clinical trials. However, protein-based artificial enzymes can be immunogenic, prone to intracellular modifications, and the treatment may not be viable after few months.We propose a novel nanotechnology-based approach for the treatment of CBS deficiency. Carbon nanomaterials with multiple unsaturated carbons provide an excellent scaffold for engineering enzyme mimicking catalysts. We have designed carbon nanomaterial based catalytic artificial enzymes (CAEs) by surface engineering to mimic metabolic enzymes that catabolize Hcy under physiological conditions. Using a combination of paper chromatography and H1-NMR, our lab has shown that CAE can breakdown homocysteine and produce hydrogen sulfide similar to CGL enzyme. The degree of surface functionalization as well as surface curvature has profound effect on specificity and catalysis. We have shown that CAE can enter cells and lower homocysteine levels in cellular models. In preliminary studies, CAE was able to lower serum homocysteine levels in a murine model. Further studies will involve safety assessments of CAE as a treatment for HCU.

Effects of dietary protein level on liver lipid deposition, bile acid profile and gut microbiota composition of growing pullets

The current study investigated the effects of dietary crude protein (CP) level on the liver lipid metabolism, gut microbiota, and bile acids (BA) profiles of growing pullets. Roman growing pullets (N = 180, 13-wk-old) were divided into 3 treatments groups with 6 replicates in each group and 10 hens in each replicate and provided 3 different dietary CP level diet treatments. The diet treatments included: a high-protein diet (15.5% CP, HP group), a medium-protein diet (14.5% CP, MP group), and a low-protein diet (13.5% CP, LP group). Compared with HP group, LP group significantly increased the lipid contents in the body (such as Breast intramuscular fat [BIMF], Leg intramuscular fat [LIMF], Percentage of abdominal fat [PAF], liver triglyceride [TG] and liver cholesterol [TC]), and the lipid metabolism-related parameters in serum (such as cholesterol (TC), high density lipoprotein cholesterol [HDL-C], low density lipoprotein cholesterol [LDL-C], very low density lipoprotein [VLDL]), and the mRNA expression of lipid metabolism-related genes (such as fatty acid synthase [FAS], CCAAT/enhancer binding protein β [C/EBPβ], and fatty acid translocase [FAT/CD6]) (P < 0.05). In addition, LP group significantly reduced the contents of lithocholic acid (LCA), isoLCA, and ursodesoxycholic acid (UDCA), and increased the deoxycholic acid (DCA) content compared with HP group (P < 0.05). The effects of LCA on lipid deposition were confirmed in chicken preadipocyte cell line (CPI), in which LCA supplementation significantly decreased the relative expression of PPARγ, FAS, acyl-CoA carboxylase (ACC) and SREBP-1c (P < 0.05). Correlation analysis further revealed a significant association between BA profiles and lipid metabolism-related parameters. Furthermore, 16S rRNA gene sequencing indicated that dietary protein level can significantly affect the richness, diversity, and composition of cecal microbiota in growing pullets. LP group significantly increased the abundance of Bacteroidetes and significantly decreased the abundance of Firmicutesa compared with the HP group. In summary, low protein diet in growing pullets influence the liver lipid metabolism through changing the gut microbiota and liver BA metabolism.

Larval diet impacts black soldier fly (Diptera: Stratiomyidae) thermal tolerance and preference.

Thermal tolerance and preference are key parameters impacting agricultural production systems. In this study, the impact of larval diet on black soldier fly thermal tolerance and preference across life-stages and sexes was examined. Larvae were fed either a low-protein high-carbohydrate synthetic diet (i.e., P7C35), a high-protein low-carbohydrate synthetic diet (i.e., P35C7), or the Gainesville diet (i.e., C) as a control and reference. Our results demonstrate that the impacts of larval diet on black soldier fly thermal tolerance and preference could be stage and sex specific. The mean heat knockdown temperatures (HKT) ranged between 46.6 and 47.9 °C. Synthetic diets resulted in greater HKT and the difference decreased form larvae (e.g., ∼1 °C) to adults (e.g., ∼0.2 °C). The mean chill-coma recovery time (CCRT) ranged between 8.3 and 21.6 min. Not much differences were detected between diets, but CCRT became longer from larvae to adults. The mean thermal preference ranged between 13.6 and 29.5 °C. Larvae fed synthetic diets preferred much lower temperatures than the control diet. A bimodal distribution was observed for adults regardless of sex. Differences on body mass, lipid, and protein contents were detected among diets; however, more research should be done before any conclusions can be linked to their thermal traits. These findings highlight the importance of considering the ingredients and nutritional makeup of larval diets when optimizing temperature management protocols for mass production of black soldier flies. Conversely, specific diets can be developed to promote survival under extreme rearing temperatures.

Effects of Probiotics on Liver and Kidney Function Parameters

This study aimed to study the effects of probiotics on liver and kidney function parameters. An in vitro study was used to identify food-grade probiotics for human consumption. As far as probiotic strains used, B. longum subspecies infantis, L. acidophilus, as well as B. bifidum are all GRAS (Generally Recognized as Safe). Over the course of six months, 100 patients with CKD and Liver disease 50 patients were without treatment and 50 patients were given two capsules each morning and evening containing 2.5*109 CFU B. longum subspecies infantis, L. acidophilus, as well as B. bifidum at a ratio of 1:1:1, and 50 normal indivisuals were used in this study. Pre-test nutritionists recommended the participants to eat low-protein diets and to avoid any lifestyle or dietary changes throughout the experiment time. Blood was collected for evaluation of AST, ALT, Total protein, Urea, and creatinine levels in both patients and normal. These kits were obtained from Biolabo company, these were done according to company instructions. The results showed that the probiotics had a therapeutics effect which causes a significant difference in all parameters in treated patients as compared with patients that were not treated. In conclusion, Probiotics have therapeutic effects on the injured kidney and the liver, which are indicated by decreasing the liver and kidney functions.

Effects of Dietary Glutamate on the Growth Performance and Antioxidant Capacity of Juvenile Chinese Mitten Crab (Eriocheir sinensis)

In order to explore the effects of glutamate on the growth performance, antioxidant capacity and protein metabolism of juvenile Chinese mitten crab, 0%, 1% and 2% glutamate were supplemented to low protein (30%) and normal protein (35%) diets, respectively. There were 5 parallel tanks in each treatment, and the feeding duration was 8 weeks. The results showed that dietary glutamate did not significantly affect the weight gain of Chinese mitten crab. Diets supplemented with 2% glutamate significantly decreased the crude protein of crabs. The T-AOC of crabs fed the 30% protein diets was significantly lower than crabs fed the 35% protein diets. At 30% protein level, the superoxide dismutase (SOD) activity significantly increased with the increase in glutamate content. Dietary glutamate significantly down-regulated the relative expressions of mTOR, PI3K, S6K1 and 4EBP at 35% protein level. In conclusion, dietary glutamate cannot significantly increase the growth of Chinese mitten crab, but it can improve the antioxidant capacity in Chinese mitten crab under low protein conditions.

Precise evaluation of the nutritional value of yeast culture and its effect on pigs fed low-protein diets

The purpose of the present study was to assess the nutritional value of yeast culture (YC) and to explore the effect of YC on growth performance and health of piglets fed low-protein (LP) diets. In Exp.1, 12 growing barrows were allocated into control diet and YC diet treatments to determine the available energy of YC. Results showed that the digestible energy and metabolizable energy of YC are 12.12 and 11.66 MJ/kg dry matter (DM), respectively. In Exp.2, 12 growing barrows were surgically equipped with a T-cannula near the distal ileum and were assigned to 2 dietary treatments (nitrogen-free diet and YC diet), and the amino acid digestibility of YC was determined. In Exp.3, a total of 96 weaned piglets were randomly divided into 4 treatments, including LP basal diet (Basal), Basal+0.5% YC (0.5%YC), Basal+1.0% YC (1%YC), and Basal+1.5% YC (1.5%YC). The results were as follows: YC supplementation linearly improved the weight gain and feed intake ratio (P < 0.001), linearly increased the activity of glutathione peroxidase on d 14 (P = 0.032) and linearly decreased the concentration of malondialdehyde on d 14 (P = 0.008) and d 32 (P = 0.004) in serum, and linearly decreased the concentration of total short-chain fatty acid on d 14 in feces (P = 0.045). Compared with other treatments, 1.5%YC group showed a greater abundance of various probiotics, such as Prevotellaceae, Prevotella and Turicibacter. In Exp.4, twelve growing barrows with an ileal T-cannula were randomly assigned to Control and 1.5%YC treatments to clarify the impact of YC supplementation on nitrogen balance and nutrient digestibility. Results showed that YC had no significant effect on nitrogen efficiency and nutrient digestibility, except for trend of reducing the total tract digestibility of organic matter (P = 0.067). In conclusion, the present study assessed the digestible and metabolizable energy values (12.12 and 11.66 MJ/kg DM, respectively) and standardized ileal digestibility of amino acid (from 43.93% to 82.65%) of YC in pig feed and demonstrated that moderate supplementation of YC (1.5% of diet) can effectively improve feed conversion efficiency, enhance antioxidant capacity, and promote a balanced gut microbiota in piglets.

Addition of Spray-Dried Plasma in Phase 2 Diets for Weanling Pigs Improves Growth Performance, Reduces Diarrhea Incidence, and Decreases Mucosal Pro-Inflammatory Cytokines.

The hypothesis that pigs fed a low crude protein (CP) diet with 6% spray-dried plasma (SDP) in phase 1 will have improved growth and intestinal health if the phase-2 diet contains 2.5% SDP was tested. Three hundred weaned pigs were used. Growth performance, feces, blood, and intestinal tissue were evaluated. Pigs fed 6% SDP in phase 1 had improved average daily gain (ADG) and final body weight (BW), but had reduced villus-height-to-crypt-depth ratio in phase 2 if 2.5% SDP was included in the normal-CP diet (p < 0.05), but not in the low-CP diet. Diarrhea incidence was less (p < 0.05) with 2.5% SDP in the phase 2 diet and for the low-CP diet. Ileal mucosa interleukin-1α (IL-1α) and IL-1β decreased (p < 0.05) for pigs fed the phase-1 diet with 6% SDP compared with pigs fed the diet without SDP. Addition of 2.5% SDP in phase 2 reduced (p < 0.05) IL-1β compared with the diet without SDP. Although the combination of SDP and low CP did not affect intestinal health in phase 2, diarrhea incidence and pro-inflammatory cytokines were reduced in pigs fed SDP in phase 1 or phase 2 or if a low-CP diet was fed.

Rumen microbiota helps Tibetan sheep obtain energy more efficiently to survive in the extreme environment of the Qinghai-Tibet Plateau.

T-sheep and H-sheep exhibit different environmental adaptability and production performance. The rumen microbiome has co-evolved with hosts and plays a vital role in nutrient digestion and energy metabolism. In our previous study, we found that T-sheep have a higher efficiency in energy metabolism than H-sheep, but the rumen microbial community remains unclear. In this study, we determined the rumen bacterial profile and rumen fermentation parameters to reveal the bacterial profiles and predictive functions among breeds and diets with four different energy levels, as well as the correlation between bacterial profiles and rumen fermentation characteristics. The results showed that the rumen total volatile fatty acids (VFAs), acetate, butyrate, total branched-chain VFAs, iso-butyrate, and iso-valerate were higher in T-sheep than H-sheep. The alpha diversity of ruminal bacteria is not affected by dietary energy, but it shows a distinction between the sheep breeds. Specifically, T-sheep rumen bacteria exhibit higher alpha diversity than H-sheep. The beta diversity of ruminal bacteria is not influenced by dietary energy or sheep breeds, indicating similar communities of ruminal bacteria between different diets and sheep breeds. The phyla of Bacteroidetes and Firmicutes predominate in the rumen, with a higher relative abundance of Firmicutes observed in T-sheep than H-sheep. The two most abundant genera in the rumen were Prevotella 1 and Rikenellaceae RC9 gut group. Prevotella 1 is the predominant bacterial genus in the rumen of H-sheep, while the Rikenellaceae RC9 gut group dominates in the rumen of T-sheep. Microbial co-occurrence network analysis reveals that variations in rumen fermentation characteristics result from differences in module abundance, with a higher abundance of VFA-producing modules observed in the rumen of T-sheep. Microbial function prediction analysis showed that dietary energy rarely alters the functional composition of rumen bacteria. However, there were differences in the functions of rumen bacteria between sheep breeds, with T-sheep showing a greater emphasis on energy metabolism-related functions, while H-sheep showed a greater emphasis on protein metabolism-related functions. These findings provide evidence of the special rumen microbial community that helps T-sheep efficiently obtain energy from low-protein and low-energy diets, enabling them to survive in the extreme environment of the Qinghai-Tibet Plateau.

Puerarin Affects 1HMR Spectroscopy Quantified Hepatic Fat Signal Fraction in Intrauterine Growth Restricted Rats.

This study aimed to investigate the impact of puerarin early intervention on growth parameters and Hepatic Fat Signal Fraction (HFF) quantification in Intrauterine Growth Restricted(IUGR)rats through Proton Magnetic resonance spectroscopy (1H-MRS). Pregnant rats were divided into three groups: control, IUGR with puerarin treatment, and IUGR without treatment. The treatment and nontreatment groups were received a low-protein diet during pregnancy, while the control group received a normal diet. After birth, pups in the treatment group received a unilateral intraperitoneal injection of 50 mg/kg/d puerarin. Male rats were evaluated at 3,8 and 12 weeks, including measurements of weight, body length and waist circumference and body mass index (BMI). Conventional magnetic resonance imaging and 1HMRS were conducted using a 3.0 T whole-body MR scanner. Newborn pups in the treatment and non-treatment groups showed significantly lower body weight, BMI, and body length at 3 weeks compared to the control group. However, there were no significant differences in HFF and waist circumference between the three groups at 3 weeks. At 8 and 12 weeks post-delivery, significant differences in body weight, BMI, waist circumference were observed in newborn pups of IUGR non-treatment rats compared to the control group. In contrast, there were no significant differences in body weight, BMI, waist circumference between the treatment group and the control group at 8 and 12 weeks. Moreover, the treatment group exhibited notably higher HFF compared to the control group at both time points. At 12 weeks post-birth, a significant difference in HFF was observed between the IUGR non-treatment and treatment groups, although no significant difference was found at 8 weeks. Early intervention with puerarin following birth has a significant impact on liver fat content and may potentially reduce adult obesity among IUGR rats.

Beneficial Effects of Ketoanalogues on the Evolution of Renal Function and Bone Mineral Disorders in Patients with Advanced Chronic Kidney Disease: A Pilot Study.

The supplementation with Ketoanalogues in patients on very low-protein diets has shown a favorable effect on the evolution of renal function. The aim of the present study was to evaluate the progression of renal function in advanced chronic kidney disease patients on a low-protein diet (&lt;0.8 g/kg/d) with or without additional Ketoanalogues. The primary criterion is the evolution of the renal function at 6, 12, and 24 months for the two groups. The secondary criteria comprise the evolution of the body weight, mean blood pressure, 24-h proteinuria, salt and protein consumption, energy consumption, hemoglobin levels, serum albumin, prealbumin, C-reactive protein, liver function tests, serum electrolyte and phosphate levels, parathormone as well as calcium levels at the same time periods. There was a significant nephroprotective effect of the Ketoanalogues after 12 and 24 months with no differences in the protein consumption between the two groups. Mean blood pressure, hemoglobin levels, 24-hour proteinuria, serum electrolyte, liver function tests, salt and protein consumption, and serum albumin and prealbumin did not present any significant differences. Serum bicarbonate and calcium levels were higher while serum phosphate and parathormone levels were lower in the Ketoanalogue group at all follow-up time points. During the 24-month follow-up period, 4 patients from the Ketoanalogue group and 8 patients from the control group quit the study. A low-protein diet supplemented with Ketoanalogues exerts significant nephroprotective effects and better bone mineral metabolism parameters compared to a low-protein diet only.

Effect of the supplementation of N-acetylglutamate and patchouli extract on piglets fed on a low protein diet

The livestock industry faces challenges such as limited protein feed resources, suboptimal nitrogen utilization efficiency, and environmental impacts. Reducing the crude protein content in piglet diets has been shown to alleviate these issues, offering benefits to both animal welfare and environmental sustainability. However, low-protein (LP) diets can negatively affect piglet health and growth, necessitating strategies to mitigate these effects. The study aimed to explore the effects of supplementing LP diets with N-acetylglutamate (NAG) and Patchouli (PTC) on the health and growth of weaned piglets, focusing on growth metrics, antioxidant capabilities, intestinal barrier integrity, and inflammatory response. One hundred twenty healthy piglets were randomly assigned to five dietary groups, including a standard control diet (CON), an LP diet, and LP diets supplemented with NAG, PTC, or both. The trial lasted four weeks, and the piglets' growth, immune response, antioxidant status, and intestinal health were assessed. Piglets on the LP diet had lower final body weights and average daily weight gains. However, supplementation with NAG and PTC improved antioxidant defense, reduced inflammation, and enhanced intestinal health, as evidenced by increased VEGF-A expression in the small intestine epithelium (p < 0.05). The addition of NAG and PTC to LP diets can improve the health and growth of weaned piglets, suggesting a potential strategy for managing the challenges associated with LP diets. This research provides valuable insights for the livestock industry, indicating that the use of natural additives like NAG and PTC can help maintain piglet health and growth while reducing the environmental impact of high-protein diets. Further research is needed to optimize these strategies for widespread application.

Plant-based diet in hyperkalemic chronic kidney disease patients receiving sodium zirconium cyclosilicate: a feasibility clinical trial

BackgroundPlant-based diets (PBD) may induce hyperkalemia in chronic kidney disease (CKD) patients. ObjectivesWe explored the safety and feasibility of PBD in hyperkalemic CKD patients receiving the potassium binder sodium zirconium cyclosilicate (SZC). MethodsIn the current 6-wk trial, 26 hyperkalemic patients with CKD stage 4–5 not on dialysis received a low-protein low-potassium diet plus SZC for 3 wk and then a PBD with high potassium content delivered as a weekly food basket while continuing SZC for subsequent 3 wk. Plasma potassium was monitored weekly and SZC was titrated to achieve normokalemia. The 24-h urine excretion of potassium and sodium, 24-h food records, dietary quality, nutritional status, Bristol stool scale, Quality of life (QoL), and renal treatment satisfaction were assessed at baseline (week 0), week 3, and week 6. ResultsMean plasma potassium decreased from 5.5 to 4.4 mEq/L within 48–72 h after baseline, then rose to 4.7–5.0 mEq/L throughout the remaining study period following dose adjustments of SZC that matched the increased potassium intake of PBD from week 3 to week 6. Over the study period, 24-h urinary potassium excretion decreased from week 0 to week 3 and increased from week 3 to week 6. During the study, 58% of patients had fasting plasma potassium between 3.5 and 5.0 mEq/L and there was no episode of plasma potassium >6.5 mEq/L or <3.0 mEq/L during the study. P-carbon dioxide increased from baseline until week 6 (21 ± 2 to 23 ± 2 mEq/L; P = 0.002; mean ± SD), whereas remaining laboratory values remained unchanged. Fiber intake, dietary quality, the domain physical functioning from QoL, and 1 question of renal treatment satisfaction improved, whereas stool type and frequency did not change after starting PBD. ConclusionsPBD in hyperkalemia-prone CKD patients receiving SZC improved dietary quality and increased the intake of healthy foods, whereas plasma potassium concentration remained stable within normal values for most patients. Trial registration numberThis trial was registered at the https://clinicaltrials.gov/study/NCT04207203 as NCT04207203.

Impact of Quantity and Type of Dietary Protein on Cardiovascular Disease Risk Factors Using Standard and Network Meta-analyses of Randomized Controlled Trials.

Higher protein diets (HPDs) have shown favorable outcomes on weight maintenance and body-composition management; however, their protective effects against cardiovascular diseases (CVDs) remain uncertain and contentious. Furthermore, it is important to consider the influence of other macronutrients in the diet and type of dietary protein when studying HPDs, because this aspect has been overlooked in previous studies. We assessed the impacts of quantity and type of dietary protein on CVD risk factors. A database search was conducted in PubMed, Embase, CINAHL, Web of Science, and Cochrane Library and a total of 100 articles met the eligibility criteria. Extracted data from 100 articles were analyzed using standard meta-analysis, and 41 articles were also analyzed using network meta-analysis. In the standard meta-analysis, an HPD had significant favorable effects on systolic blood pressure (SBP) (mean difference [MD] = -1.51 mmHg; 95% CI: -2.77, -0.25), diastolic blood pressure (DBP) (MD = -1.08 mmHg; 95% CI: -1.81, -0.35), and flow-mediated dilation (MD = 0.78%; 95% CI: 0.09, 1.47) compared with lower protein diets. The further network meta-analysis supported that the high-protein, high-carbohydrate, low-fat diet was the most recommended diet to ensure a maximum decrease in SBP, DBP, total cholesterol (TC), and low-density-lipoprotein cholesterol (LDL-C). In comparison to animal-protein-rich diets, plant-protein-rich diets (PPRs) exhibited a significant favorable effects on improving TC (MD = -0.12 mmol/L; 95% CI: -0.19, -0.05), triglyceride (MD = -0.05 mmol/L; 95% CI: -0.09, -0.01), LDL-C (MD = -0.11 mmol/L; 95% CI: -0.18, -0.04), and high-density-lipoprotein cholesterol (MD = 0.03 mmol/L; 95% CI: 0.02, 0.04) levels. Consumption of HPDs and PPRs supports improvements in vascular health and lipid-lipoprotein profiles, respectively. Furthermore, macronutrient composition should be carefully designed in the dietary approach to maximize the effectiveness of HPDs in improving CVD risk factors. PROSPERO registration no. CRD42022369931.

Effects of different energy levels in low-protein diet on liver lipid metabolism in the late-phase laying hens through the gut-liver axis

BackgroundThe energy/protein imbalance in a low-protein diet induces lipid metabolism disorders in late-phase laying hens. Reducing energy levels in the low-protein diet to adjust the energy-to-protein ratio may improve fat deposition, but this also decreases the laying performance of hens. This study investigated the mechanism by which different energy levels in the low-protein diet influences liver lipid metabolism in late-phase laying hens through the enterohepatic axis to guide feed optimization and nutrition strategies. A total of 288 laying hens were randomly allocated to the normal-energy and normal-protein diet group (positive control: CK) or 1 of 3 groups: low-energy and low-protein diet (LL), normal-energy and low-protein diet (NL), and high-energy and low-protein diet (HL) groups. The energy-to-protein ratios of the CK, LL, NL, and HL diets were 0.67, 0.74, 0.77, and 0.80, respectively.ResultsCompared with the CK group, egg quality deteriorated with increasing energy intake in late-phase laying hens fed low-protein diet. Hens fed LL, NL, and HL diets had significantly higher triglyceride, total cholesterol, acetyl-CoA carboxylase, and fatty acid synthase levels, but significantly lower hepatic lipase levels compared with the CK group. Liver transcriptome sequencing revealed that genes involved in fatty acid beta-oxidation (ACOX1, HADHA, EHHADH, and ACAA1) were downregulated, whereas genes related to fatty acid synthesis (SCD, FASN, and ACACA) were upregulated in LL group compared with the CK group. Comparison of the cecal microbiome showed that in hens fed an LL diet, Lactobacillus and Desulfovibrio were enriched, whereas riboflavin metabolism was suppressed. Cecal metabolites that were most significantly affected by the LL diet included several vitamins, such as riboflavin (vitamin B2), pantethine (vitamin B5 derivative), pyridoxine (vitamin B6), and 4-pyridoxic acid.ConclusionA lipid metabolism disorder due to deficiencies of vitamin B2 and pantethine originating from the metabolism of the cecal microbiome may be the underlying reason for fat accumulation in the liver of late-phase laying hens fed an LL diet. Based on the present study, we propose that targeting vitamin B2 and pantethine (vitamin B5 derivative) might be an effective strategy for improving lipid metabolism in late-phase laying hens fed a low-protein diet.

Low-Protein Diets Could Be Effective and Safe in Elderly Patients with Advanced Diabetic Kidney Disease.

Low-protein diets (LPDs) seem to improve metabolic complications of advanced CKD, thus postponing kidney replacement therapy (KRT) initiation. However, the nutritional safety of LPDs remains debatable in patients with diabetic kidney disease (DKD), especially in the elderly. This is a sub-analysis of a prospective unicentric interventional study which assessed the effects of LPD in patients with advanced DKD, focusing on the feasibility and safety of LPD in elderly patients. Ninety-two patients with DKD and stable CKD stage 4+, proteinuria >3 g/g creatininuria, good nutritional status, with confirmed compliance to protein restriction, were enrolled and received LPD (0.6 g mixed proteins/kg-day) supplemented with ketoanalogues of essential amino acids for 12 months. Of the total group, 42% were elderly with a median eGFR 12.6 mL/min and a median proteinuria 5.14 g/g creatininuria. In elderly patients, proteinuria decreased by 70% compared to baseline. The rate of kidney function decline was 0.1 versus 0.5 mL/min-month before enrolment. Vascular events occurred in 15% of cases, not related to nutritional intervention, but to the severity of CKD and higher MAP. LPDs seem to be safe and effective in postponing KRT in elderly patients with advanced DKD while preserving the nutritional status.

Dietary Crude Protein Reduction with Addition of Crystalline Amino Acids in Growing Pekin Ducks Housed in Cascading Cages: Influence on Growth Performance, Carcass Traits, and Apparent Nutrient Digestibility

The intensive raising model for meat duck production has widely adopted cascading cages. However, investigations on low-protein diets for Pekin ducks under this model are scarce. Thus, a 3 × 6 factorial experiment was conducted using six dietary crude protein (CP) levels (17.61%, 16.25%, 15.34%, 14.55%, 13.38%, and 12.64%, analyzed) and three cage layers (lower, middle, and upper). The study aimed to examine the effects of dietary CP reduction with crystalline amino acid supplementation on growth performance, carcass traits, and apparent nutrient digestibility in growing Pekin ducks from 21 to 42 days of age housed at different cage layers. A total of 1620 21-day-old Pekin ducks were randomly divided into 18 groups, each with six replicates of 15 ducks per replicate. Ducks were distributed across different cage layers and were fed one of six experimental diets, respectively, each varying in dietary CP levels but maintaining similar dietary energy and amino acid profiles. The results showed that the reduction in dietary CP levels affected growth performance (p &lt; 0.05), while weight gain, feed intake, and feed/gain of Pekin ducks had no difference among 17.61%, 16.25%, and 15.34% CP groups (p &gt; 0.05). As dietary CP decreased, abdominal fat yield increased (p &lt; 0.05), but breast and leg meat yields were unaffected (p &gt; 0.05). CP intake, nitrogen intake, and nitrogen excretion decreased linearly (p &lt; 0.05) with decreasing dietary CP levels, while apparent nutrient digestibility in Pekin ducks increased proportionally (p &lt; 0.05). Additionally, body weight, weight gain, feed intake, CP intake, nitrogen intake, and nitrogen excretion of Pekin ducks decreased (p &lt; 0.05) due to different cage layers, while carcass characteristics remained unaffected by cage layer (p &gt; 0.05). In summary, it is feasible to reduce the dietary CP level with crystalline amino acid supplementation in growing Pekin ducks from 21 to 42 days of age housed in cascading cages, while the cage layers affected growth performance of ducks. Based on broken-line models, it was determined that the optimal dietary CP requirement for achieving maximum weight gain and feed efficiency in growing Pekin ducks is approximately 15%.

CHARACTERISTICS OF IMMUNOREACTIVITY IN THE RAT UNDER CONDITIONS OF TOXIC INJURY WITH ACETAMINOPHEN

The aim of this work was to to determine the integral leukocyte indices in animals with toxic damage by acetaminophen on the background of protein deficiency. The study was conducted on 4 groups of animals: Group I - control animals (K); II – rats kept on a low-protein diet (LPD); ІІІ – animals with acetaminophen-induced liver injury receiving complete ration (AII); IV – animals with acetaminophen-induced liver injury that were previously maintained on semi-synthetic low-protein ration (LPD/AII). Preparation of blood smears, their fixation and staining was carried out by the generally accepted method. The ratio of different types of leukocytes in stained blood smears was calculated using a standard method using a leukocyte counter and a microscope (eyepiece × 10, objective × 100). Standard formulas were used to calculate integral hematological indices. It was established that the supply of protein in the diet is critical for the functioning of the immune system under conditions of acetaminophen intoxication, since under these conditions there is a change in leukocyte indices, in particular, the index of immunoreactivity, the index of leukocyte shift, the index of the ratio of neutrophils and lymphocytes, the index of the reactive response of neutrophils, which indicates the intensification of inflammatory processes in the body and the formation of defects in the cellular link of immunity, disruption of the mechanisms of the specific immune response and the formation of a state of endotoxicosis. The obtained results can be used to develop approaches to the early diagnosis of impaired immunoreactivity in animals with toxic damage by acetaminophen against the background of dietary protein deficiency, while the studied integral hematological indicators can be used as additional early diagnostic markers of impaired immunoreactivity and endotoxicosis. Key words: acetaminophen, dietary protein deficiency, leukocytes, immunoreactivity indices

Effects of Dietary Protein Intake Levels on Peripheral Circadian Rhythm in Mice.

The regulation of the circadian clock plays an important role in influencing physiological conditions. While it is reported that the timing and quantity of energy intake impact circadian regulation, the underlying mechanisms remain unclear. This study investigated the impact of dietary protein intake on peripheral clocks. Firstly, transcriptomic analysis was conducted to investigate molecular targets of low-protein intake. Secondly, mPer2::Luc knock-in mice, fed with either a low-protein, normal, or high-protein diet for 6 weeks, were analyzed for the oscillation of PER2 expression in peripheral tissues and for the expression profiles of circadian and metabolic genes. Lastly, the candidate pathway identified by the in vivo analysis was validated using AML12 cells. As a result, using transcriptomic analysis, we found that the low-protein diet hardly altered the circadian rhythm in the central clock. In animal experiments, expression levels and period lengths of PER2 were different in peripheral tissues depending on dietary protein intake; moreover, mRNA levels of clock-controlled genes and endoplasmic reticulum (ER) stress genes were affected by dietary protein intake. Induction of ER stress in AML12 cells caused an increased amplitude of Clock and Bmal1 and an advanced peak phase of Per2. This result shows that the intake of different dietary protein ratios causes an alteration of the circadian rhythm, especially in the peripheral clock of mice. Dietary protein intake modifies the oscillation of ER stress genes, which may play key roles in the regulation of the circadian clock.

Effects of additional physical exercise on the nutritional status and disease progression during the low-protein diet in Chronic Kidney Disease Patients: a systematic review and meta-analysis.

Low-protein diet (LPD) is the core of dietary and nutritional therapy for non-dialysis chronic kidney disease (CKD) patients. In addition, physical exercise could prevent and treat various illnesses and chronic diseases. The objective of the study was to search for and appraise evidence on the effect of additional physical exercise on patients' nutritional status and indicators of disease progression when compared with the LPD alone. PubMed Central, Embase, Cochrane, and Web of Knowledge for randomized controlled trials (published between January 1, 1956 and May 17, 2023) were searched. A total of 8698 identified studies, 9 were eligible and were included in our analysis (N = 250 participants). Compared with the LPD alone, additional physical exercise reduced serum creatinine by a mean of -0.21 mg/dL (95% CI -0.39 to -0.03) in CKD patients. Similarly, blood pressure decreased after physical exercise, with systolic blood pressure decreasing by -7.05 mm Hg (95% CI -13.13 to -0.96) and diastolic blood pressure decreasing by -5.31 mm Hg (95% CI -7.99 to -2.62). Subgroup analyses revealed that resistance exercise (RE) was effective in decreasing estimated glomerular filtration rate (eGFR) of -1.71 mL/min per 1.73 m² (95% CI -3.29 to -0.14). In addition, the VO2peak increasing by 2.41 mL/kg/min (95% CI 0.13 to 4.70) when physical exercise was continued for 24 weeks. The above results suggest that the LPD with additional physical exercise care is more beneficial for patients with CKD.