Sodium Butyrate Attenuates Diabetic Kidney Disease Partially via Histone Butyrylation Modification

Impact of high-fat diet on ovarian epigenetics: Insights from altered intestinal butyric acid levels

Objective

To investigate the effects of a high-fat diet (HFD) on the gut bacterium Roseburia intestinalis and butyric acid levels, and to assess their impact on ovarian function and epigenetic markers in mice.

Methods

A total of 20 female ICR mice aged 4 weeks were randomly assigned to two groups and fed either a control diet (CD) or an HFD for 36 weeks. Post-intervention, ileal contents were analyzed for the quantification of butyric acid using ELISA, while feces were obtained for Roseburia intestinalis expression assessment via qPCR. Histological evaluations of intestinal and ovarian tissues included H&E and Alcian Blue-Periodic Acid Schiff (AB-PAS) staining, alongside immunohistochemical analysis for F4/80, and immunofluorescent detection of Occludin, ZO-1, 5 mC, and H3K36me3. Ovarian health was assessed through follicle counts and morphological evaluations. Statistical analyses were performed using GraphPad Prism 8.0, with P < 0.05 considered significant.

Results

After 36 weeks, the HFD group showed significantly higher body weight compared to the CD group (P < 0.01). The HFD led to a decrease in Roseburia intestinalis and butyric acid levels, a reduction in intestinal goblet cells, and an increase in intestinal inflammation. Histological analyses revealed impaired ovarian follicular development and enhanced inflammation in the HFD mice, with immunofluorescent staining showing downregulation of the ovarian epigenetic markers 5 mC and H3K36me3.

Conclusion

Our study demonstrates that long-term HFD negatively impacts ovarian function and epigenetic regulation. We found decreased levels of the gut bacterium Roseburia intestinalis and its metabolite, butyric acid, which contribute to these adverse effects. Additionally, the associated intestinal inflammation and compromised mucosal barrier may contribute to these adverse outcomes on female reproductive health.

[Bmal1 mediates the neuroprotective effect of sodium butyrate in a mouse model of Parkinson's disease]

OBJECTIVE

To investigate the mechanisms that mediate the neuroprotective effect of the intestinal microbial metabolite sodium butyrate (NaB) in a mouse model of Parkinson's disease (PD) via the gut-brain axis.

METHODS

Thirty-nine 7-week-old male C57BL/6J mice were randomized equally into control group, PD model group, and NaB treatment group. In the latter two groups, PD models were established by intraperitoneal injection of 30 mg/kg 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) once daily for 5 consecutive days, and normal saline was injected in the control group. After modeling, the mice received daily gavage of NaB (300 mg/kg) or an equal volume of saline for 14 days. Behavioral tests were carried out to assess the changes in motor function of the mice, and Western blotting was performed to detect the expressions of tyrosine hydroxylase (TH) and α-synuclein (α-syn) in the striatum and nuclear factor-κB (NF-κB), tumor necrosis factor (TNF-α), interleukin 6 (IL-6), and the tight junction proteins ZO-1, Occludin, and Claudinin the colon. HE staining was used to observe inflammatory cell infiltration in the colon of the mice. RNA sequencing analysis was performed to identify the differentially expressed genes in mouse colon tissues, and their expressions were verified using qRT-PCR and Western blotting.

RESULTS

The mouse models of PD with NaB treatment showed significantly increased movement speed and pulling strength of the limbs with obviously upregulated expressions of TH, Occludin, and Claudin and downregulated expressions of α-syn, NF-κB, TNF-α, and IL-6 (all P < 0.05). HE staining showed that NaB treatment significantly ameliorated inflammatory cell infiltration in the colon of the PD mice. RNA sequencing suggested that Bmal1 gene probably mediated the neuroprotective effect of NaB in PD mice (P < 0.05).

CONCLUSION

NaB can improve motor dysfunction, reduce dopaminergic neuron loss in the striatum, and ameliorate colonic inflammation in PD mice possibly through a mechanism involving Bmal1.

Mechanism of sodium butyrate, a metabolite of gut microbiota, regulating cardiac fibroblast transdifferentiation via the NLRP3/Caspase-1 pyroptosis pathway

BACKGROUND

Cardiac fibroblasts (CFs) are activated after initial injury, and then differentiate into myofibroblasts (MFs), which play a pivotal role as the primary mediator cells in pathological remodeling. Sodium butyrate (NaB), being a metabolite of gut microbiota, exhibits anti-inflammatory property in local therapies on sites other than the intestine. Thus, this study aimed to probe the mechanism by which NaB regulates CFs transdifferentiation through the NLRP3/Caspase-1 pyroptosis pathway.

METHODS

CFs were cultured in vitro and induced into MFs by TGFβ1. CFs were identified by immunofluorescence labelling technique of vimentin and α-SMA, followed by treatment with NaB or NLRP3 inflammasome inhibitor (CY-09) and its activator [nigericin sodium salt (NSS)]. The expression levels of α-SMA, GSDMD-N/NLRP3/cleaved Caspase-1 proteins, and inflammatory factors IL-1β/IL-18/IL-6/IL-10 were determined using immunofluorescence, Western blot and ELISA. Cell proliferation and migration were evaluated using the CCK-8 assay and the cell scratch test, respectively.

RESULTS

Following the induction of TGFβ1, CFs exhibited increased expression levels of α-SMA proteins and IL-6/IL-10, as well as cell proliferative and migratory abilities. TGFβ1 induced CFs to differentiate into MFs, while NaB inhibited this differentiation. NaB inactivated the NLRP3/Caspase-1 pyroptosis pathway. CY-09 demonstrated inhibitory effects on the NLRP3/Caspase-1 pyroptosis pathway, leading to a reduction in TGFβ1-induced CFs transdifferentiation. NSS activated the NLRP3/Caspase-1 pyroptosis pathway, and thus partially counteracting the inhibitory effect of intestinal microbiota metabolite NaB on CFs transdifferentiation.

CONCLUSION

NaB, a metabolite of the gut microbiota, inhibited the activation of the NLRP3/Caspase-1 pyroptosis pathway in TGFβ1-induced CFs, repressed the transdifferentiation of CFs into MFs.

Intestinal Fibrogenesis in Inflammatory Bowel Diseases: Exploring the Potential Role of Gut Microbiota Metabolites as Modulators

Fibrosis, sustained by the transformation of intestinal epithelial cells into fibroblasts (epithelial-to-mesenchymal transition, EMT), has been extensively studied in recent decades, with the molecular basis well-documented in various diseases, including inflammatory bowel diseases (IBDs). However, the factors influencing these pathways remain unclear. In recent years, the role of the gut microbiota in health and disease has garnered significant attention. Evidence suggests that an imbalanced or dysregulated microbiota, along with environmental and genetic factors, may contribute to the development of IBDs. Notably, microbes produce various metabolites that interact with host receptors and associated signaling pathways, influencing physiological and pathological changes. This review aims to present recent evidence highlighting the emerging role of the most studied metabolites as potential modulators of molecular pathways implicated in intestinal fibrosis and EMT in IBDs. These studies provide a deeper understanding of intestinal inflammation and fibrosis, elucidating the molecular basis of the microbiota role in IBDs, paving the way for future treatments.

Association Between Dietary Fiber Intake and Prevalence of Chronic Obstructive Pulmonary Disease in a Middle-Aged and Elderly Population: a Study Based on the National Health and Nutrition Examination Survey Database

Objective

This study aimed to investigate dietary fiber (DF) intake with the prevalence of chronic obstructive pulmonary disease (COPD) in the middle-aged and elderly population through analysis of the National Health and Nutrition Examination Survey (NHANES) data.

Methods

The study utilized data from 3 cycles of the NHANES database (2007-2012). The exposure variable was DF intake, and the outcome variable was COPD prevalence. Weighted logistic regression was utilized to construct relationship models between the 2 variables. Confounding factors were adjusted, and subgroup analysis was to explore the association of DF intake with COPD. Restricted cubic spline (RCS) analysis investigated the nonlinear relationship between DF intake and COPD. Finally, mediation analysis was performed to determine whether the influence of DF intake on COPD prevalence is mediated through the alteration of white blood cell (WBC) counts.

Results

This study included a total of 7301 eligible participants aged >40 years. The results of the study indicated that an increase in DF intake significantly reduced the prevalence of COPD (odds ratio: 0.98, 95% confidence interval: 0.96-0.99, p<0.001), and DF intake was correlated with lung function indicators (e.g., forced expiratory volume in 1 second). Stratified analysis revealed that an increased DF intake significantly reduced the risk of COPD in male individuals, middle-aged individuals (aged 40-59 years), those with a body mass index ≤30 kg/m2, individuals with a history of smoking, and alcohol consumers (p<0.05). Through RCS analysis exploring the nonlinear association between DF intake and COPD prevalence, the critical threshold for the impact of DF intake on COPD prevalence was 15.10 gm. When DF intake was ≥15.10 g/d, it effectively reduced the prevalence of COPD. Mediation analysis results indicated that the WBC count partially mediated the association between DF intake and COPD, with a mediation proportion of 9.89% (p=0.006).

Conclusion

Increased DF intake was linked to decreased prevalence of COPD, particularly in men and middle-aged people. WBC counts may be an important pathway linking DF intake and COPD.

Dietary fiber intake and its association with diabetic kidney disease in American adults with diabetes: A cross-sectional study

BACKGROUND

Dietary fiber (DF) intake may have a protective effect against type 2 diabetes (T2D); however, its relationship with diabetic kidney disease (DKD) remains unclear.

AIM

To investigate the potential association between DF intake and the prevalence of DKD in individuals diagnosed with T2D.

METHODS

This cross-sectional study used data from the National Health and Nutrition Examination Survey collected between 2005 and 2018. DF intake was assessed through 24-h dietary recall interviews, and DKD diagnosis in individuals with T2D was based on predefined criteria, including albuminuria, impaired glomerular filtration rate, or a combination of both. Logistic regression analysis was used to assess the association between DF intake and DKD, and comprehensive subgroup and sensitivity analyses were performed.

RESULTS

Among the 6032 participants, 38.4% had DKD. With lower DF intake-T1 (≤ 6.4 g/1000 kcal/day)-as a reference, the adjusted odds ratio for DF and DKD for levels T2 (6.5-10.0 g/1000 kcal/day) and T3 (≥ 10.1 g/1000 kcal/day) were 0.97 (95%CI: 0.84-1.12, P = 0.674) and 0.79 (95%CI: 0.68-0.92, P = 0.002), respectively. The subgroup analysis yielded consistent results across various demographic and health-related subgroups, with no statistically significant interactions (all P > 0.05).

CONCLUSION

In United States adults with T2D, increased DF intake may be related to reduced DKD incidence. Further research is required to confirm these findings.

Epigenetically regulated inflammation in vascular senescence and renal progression of chronic kidney disease

Chronic kidney disease (CKD) and its complications, including vascular senescence and progressive renal fibrosis, are associated with inflammation. Vascular senescence, in particular, has emerged as an instrumental mediator of vascular inflammation that potentially worsens renal function. Epigenetically regulated inflammation involving histone modification, DNA methylation, actions of microRNAs and other non-coding RNAs, and their reciprocal reactions during vascular senescence and inflammaging are underappreciated. Their synergistic effects can contribute to CKD progression. Vascular senotherapeutics or pharmacological anti-senescent therapies based on epigenetic machineries can therefore be plausible options for ameliorating vascular aging and even halting the worsening of renal fibrosis. These include histone deacetylase modulators, histone methyltransferase modulators, other histone modification effectors, DNA methyltransferase inhibitors, telomerase reverse transcriptase enhancers, microRNA mimic delivery, and small molecules with microRNA-regulating potentials. Some of these molecules have already been tested and have shown anecdotal evidence for treating uremic vasculopathy and renal fibrosis, supporting the feasibility of this approach.

Sodium benzoate induces pancreatic inflammation and β cell apoptosis partially via benzoylation

Epigenetics, specifically histone post-translational modification (HPTM) induced by environmental factors, plays a crucial role in the development of diabetes. Sodium benzoate (NAB) is a widely used additive, however, its potential contribution to diabetes has been largely overlooked. In 2018, a novel HPTM called benzoylation (Kbz) induced by NAB was discovered. This modification can be catalyzed by ACSS2 (acyl-CoA synthetase short-chain member 2) and acyltransferase P300/CBP, and can be reversed by erase enzymes SIRT2. Studies have indicated that Kbz may regulate insulin secretion, although the exact molecular mechanism remains unclear. In our study, C57BL/6J mice were divided into two groups: the NC group and the 1g/kg NAB water feeding group. In vivo experiments were conducted using β-TC-6 cells, with 6 mM NAB or 100 μM benzoyl-CoA as stimuli, and 10 μM A485 (P300 inhibitor), 5 μM ACSS2 inhibitor (inhibiting benzoyl-CoA synthesis), or 5 μM AGK2 (SIRT2 inhibitor) as intervention factors. Our study found that, although the experimental concentration of NAB is below the maximum allowable concentration in food, it still damaged the insulin secretion function of C57BL/6J mice and induced inflammation and apoptosis of islet β cells. We observed significant differences in serum benzoyl-CoA levels between healthy individuals and patients with type 2 diabetes. Furthermore, NAB concentration-dependently increases benzoyl-CoA and Kbz levels. When Kbz is down-regulated using A485 and ACSS2 inhibitor, we observed a reduction in β cell inflammation, apoptosis, and insulin secretion damage. Conversely, up-regulating Kbz using AGK2 resulted in increased levels of β cell inflammation and apoptosis. In conclusion, our data suggest that NAB, despite being within the safe dose range, may be an overlooked environmental risk factor contributing to the pathogenesis of diabetes through its impact on Kbz.

Effects of short-chain fatty acids on blood glucose and lipid levels in mouse models of diabetes mellitus: A systematic review and network meta-analysis

Short-chain fatty acids (SCFAs), the main metabolites of gut microbiota, have been associated with lower blood glucose and lipid levels in diabetic mice. However, a comprehensive summary and comparison of the effects of different SCFA interventions on blood glucose and lipid levels in diabetic mice is currently unavailable. This study aims to compare and rank the effects of different types of SCFAs on blood glucose and lipid levels by collecting relevant animal research. A systematic search through PubMed, Embase, Cochrane Library, and Web of Science database was conducted to identify relevant studies from inception to March 17, 2023. Both pairwise meta-analysis and Bayesian network meta-analysis were used for statistical analyses. In total, 18 relevant studies involving 5 interventions were included after screening 3793 citations and 53 full-text articles. Notably, butyrate therapy (mean difference [MD] = -4.52, 95% confidence interval [-6.29, -2.75]), acetate therapy (MD = -3.12, 95% confidence interval [-5.79, -0.46]), and propionate therapy (MD = -2.96, 95% confidence interval [-5.66, -0.26]) significantly reduced the fasting blood glucose levels compared to the control group; butyrate therapy was probably the most effective intervention, with a surface under the cumulative ranking curve (SUCRA) value of 85.5%. Additionally, acetate plus propionate therapy was probably the most effective intervention for reducing total cholesterol (SUCRA = 85.8%) or triglyceride levels (SUCRA = 88.1%). These findings underscore the potential therapeutic implications of SCFAs for addressing metabolic disorders, particularly in type 2 diabetes mellitus.

Sodium butyrate improves mitochondrial function and kidney tissue injury in diabetic kidney disease via the AMPK/PGC-1α pathway

PURPOSE

Investigate the mechanism of how sodium butyrate (NaBut) improves mitochondrial function and kidney tissue injury in diabetic kidney disease (DKD) via the AMPK/PGC-1α pathway.

METHODS

Assess the effects of NaBut on glucose and insulin tolerance, urine, and gut microbial composition in db/db and db/m mice. Use flow cytometry and western blotting to detect the effects of NaBut on apoptosis, kidney mitochondrial function, and AMPK/PGC-1α signaling. Use HK-2 cells induced by high glucose (HG) to establish the DKD model in vitro and detect changes in the AMPK/PGC-1α signaling pathway and mitochondrial function after NaBut intervention.

RESULTS

NaBut attenuated blood glucose levels and reversed increases in urine and serum levels of glucose, BUN, Ucr, TG, TC, and UAE in db/db mice. NaBut improved insulin tolerance, reversed PGC-1α and p-AMPK expression level in the kidneys of db/db mice, and improved lipid accumulation and mitochondrial function. NaBut was able to reverse the effects of elevated glucose, compound C, and siRNA-PGC on ROS and ATP levels. Additionally, it increased protein expression of PGC-1α and p-AMPK.

CONCLUSION

NaBut activates the kidney mitochondrial AMPK/PGC-1α signaling pathway and improves mitochondrial dysfunction in DKD, thus protecting kidney tissue in vitro and in vivo.

Role of Gut Microbiota, Immune Imbalance, and Allostatic Load in the Occurrence and Development of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a prevailing complication arising from diabetes mellitus. Unfortunately, there are no trustworthy and efficacious treatment modalities currently available. In recent times, compelling evidence has emerged regarding the intricate correlation between the kidney and the gut microbiota, which is considered the largest immune organ within the human physique. Various investigations have demonstrated that the perturbation of the gut microbiota and its associated metabolites potentially underlie the etiology and progression of DKD. This phenomenon may transpire through perturbation of both the innate and the adaptive immunity, leading to a burdensome allostatic load on the body and ultimately culminating in the development of DKD. Within this literature review, we aim to delve into the intricate interplay between the gut microbiota, its metabolites, and the immune system in the context of DKD. Furthermore, we strive to explore and elucidate potential chemical interventions that could hold promise for the treatment of DKD, thereby offering invaluable insights and directions for future research endeavors.

[Role of Histone Modifications in Acute Kidney Injury Progressing to Chronic Kidney Disease]

Acute kidney injury (AKI), a clinical syndrome caused by various factors, is characterized by a rapid decline in kidney function in a short period of time. AKI affects the short-term prognosis of patients and may also induce chronic kidney disease (CKD). However, the current treatment options for AKI mainly focus on symptom management. Specific therapeutic measures available for the prevention of transition from AKI to CKD are very limited in number. Histones are basic proteins that intricately bind the DNA in chromosomes. After translation, histones undergo various modifications on their amino-terminal tails, such as methylation, acetylation, phosphorylation, ubiquitination, and lactylation, collectively forming the "histone code", which affects the expression of genes mainly by regulating the elastic structure of chromatin or recruiting specific proteins. Extensive research conducted in recent years on histone post-translational modifications (PTMs) has also sparked continuous interest in their association with the AKI-to-CKD transition. Therefore, this paper highlights the significant role of PTMs in the process of AKI developing and progressing to CKD, with a view to finding new approaches to preventing the progression of AKI to CKD.

Sodium Butyrate Ameliorates Fluorosis-Induced Neurotoxicity by Regulating Hippocampal Glycolysis In Vivo

Fluorosis can induce neurotoxicity. Sodium butyrate (SB), a histone deacetylase inhibitor, has important research potential in correcting glucose metabolism disorders and is widely used in a variety of neurological diseases and metabolic diseases, but it is not yet known whether it plays a role in combating fluoride-induced neurotoxicity. This study aims to evaluate the effect of SB on fluoride neurotoxicity and the possible associated mechanisms. The results of HE staining and Morris water maze showed that, in mice exposed to 100 mg/L fluoride for 3 months, the hippocampal cells arranged in loosely with large cell gaps and diminished in number. One thousand milligram per kilogram per day SB treatment improved fluoride-induced neuronal cell damage and spatial learning memory impairment. Western blot results showed that the abundance of malate dehydrogenase 2 (MDH2) and pyruvate dehydrogenase (PDH) in the hippocampus of fluorosis mice was increased, the abundance of pyruvate kinase M (PKM), lactate dehydrogenase (LDH), hexokinase (HK), phosphatidylinositol 3-kinase (PI3K), phosphorylated Akt (P-AKT), and hypoxia-inducible factor 1α (HIF-1α) was inhibited, and the content of lactate and ATP was decreased. SB treatment reversed the decreased glycolysis in the hippocampus of fluorosis mice. These results suggested that SB could ameliorate fluorosis-induced neurotoxicity, which might be linked with its function in regulating glycolysis as well as inhibition of the PI3K/AKT/HIF-1α pathway. Sodium butyrate ameliorates fluorosis-induced neurotoxicity by regulating hippocampal glycolysis in vivo (created with MedPeer (www.medpeer.cn)).

The roles of gut microbiota and its metabolites in diabetic nephropathy

Diabetic nephropathy (DN) is a severe microvascular complication of diabetes, which increases the risk of renal failure and causes a high global disease burden. Due to the lack of sustainable treatment, DN has become the primary cause of end-stage renal disease worldwide. Gut microbiota and its metabolites exert critical regulatory functions in maintaining host health and are associated with many pathogenesis of aging-related chronic diseases. Currently, the theory gut-kidney axis has opened a novel angle to understand the relationship between gut microbiota and multiple kidney diseases. In recent years, accumulating evidence has revealed that the gut microbiota and their metabolites play an essential role in the pathophysiologic processes of DN through the gut-kidney axis. In this review, we summarize the current investigations of gut microbiota and microbial metabolites involvement in the progression of DN, and further discuss the potential gut microbiota-targeted therapeutic approaches for DN.

Lupenone improves type 2 diabetic nephropathy by regulating NF-κB pathway-mediated inflammation and TGF-β1/Smad/CTGF-associated fibrosis

BACKGROUND

Type 2 diabetic nephropathy is a common diabetic complication and the main cause of death in patients with diabetes. Research has aimed to find an ideal drug with minimal side effects for treating this disease. Banana peel has been shown to be anti-diabetic, with lupenone isolated from banana peel exhibiting antidiabetic and anti-inflammatory activities; However, the effects of lupenone on type 2 diabetic nephropathy are largely unknown.

PURPOSE

This study aimed to investigate the ameliorative effect of lupenone on type 2 diabetic nephropathy, and its mechanism from both anti-inflammatory and anti-fibrotic perspectives.

METHODS

Spontaneous type 2 diabetic nephropathy db/db mouse models were given three levels of lupenone (24 or 12 or 6 mg/kg/d) via intragastric administration for six weeks, and irbesartan treatment was used for the positive control group. We explored the effects and mechanism of lupenone action using enzyme-linked immunosorbent assay, automatic biochemical analyzer, hematoxylin-eosin and Masson staining, real time-PCR, and western blotting. Concurrently, a high-sugar and high-fat diet combined with a low-dose streptozotocin-induced type 2 diabetic nephropathy rat model was used for confirmatory research.

RESULTS

Lupenone administration maintained the fasting blood glucose; reduced glycosylated hemoglobin, insulin, and 24 h proteinuria levels; and markedly regulated changes in biochemical indicators associated with kidney injury in serum and urine (including 24 h proteinuria, micro-albumin, N-acetyl-β-d-glucosaminidase, α1-micro-globulin, creatinine, urea nitrogen, uric acid, total protein, and albumin) of type 2 diabetic nephropathy mice and rats. Hematoxylin-eosin and Masson staining as well as molecular biology tests revealed that inflammation and fibrosis are the two key processes affected by lupenone treatment. Lupenone protected type 2 diabetic nephropathy kidneys by regulating the NF-κB-mediated inflammatory response and TGF-β1/Smad/CTGF pathway-associated fibrosis.

CONCLUSION

Lupenone has potential as an innovative drug for preventing and treating diabetic nephropathy. Additionally, it has great value for the utilization of banana peel resources.

The pathogenic role of intestinal flora metabolites in diabetic nephropathy

With the increasing incidence of diabetes, diabetic kidney disease has become a major cause of chronic kidney disease. The role of the gut microbiota in diabetes and its related complications have been extensively investigated; the modulatory effect of the gut microbiota on the host depends on several gut microbial metabolites, particularly short-chain fatty acids, secondary bile acids, and trimethylamine N-oxide. In this review, we focused on the evidence related to the pathogenic role of each of the gut microbial metabolites in diabetic nephropathy. The main novel therapies targeting the gut microbiota include probiotics, dietary prebiotics, synbiotic supplements, and faecal microbiota transplants, although there is no standard treatment principle. Further research is therefore needed to elucidate the link between gut microbes and diabetic nephropathy, and more therapeutic targets should be explored to treat diabetic nephropathy with dysbiosis of the gut microbes.

Protein posttranslational modifications in health and diseases: Functions, regulatory mechanisms, and therapeutic implications

Protein posttranslational modifications (PTMs) refer to the breaking or generation of covalent bonds on the backbones or amino acid side chains of proteins and expand the diversity of proteins, which provides the basis for the emergence of organismal complexity. To date, more than 650 types of protein modifications, such as the most well-known phosphorylation, ubiquitination, glycosylation, methylation, SUMOylation, short-chain and long-chain acylation modifications, redox modifications, and irreversible modifications, have been described, and the inventory is still increasing. By changing the protein conformation, localization, activity, stability, charges, and interactions with other biomolecules, PTMs ultimately alter the phenotypes and biological processes of cells. The homeostasis of protein modifications is important to human health. Abnormal PTMs may cause changes in protein properties and loss of protein functions, which are closely related to the occurrence and development of various diseases. In this review, we systematically introduce the characteristics, regulatory mechanisms, and functions of various PTMs in health and diseases. In addition, the therapeutic prospects in various diseases by targeting PTMs and associated regulatory enzymes are also summarized. This work will deepen the understanding of protein modifications in health and diseases and promote the discovery of diagnostic and prognostic markers and drug targets for diseases.

Acylations in cardiovascular biology and diseases, what's beyond acetylation

Metabolism regulates cardiovascular biology through multiple mechanisms, including epigenetic modifications. Over the past two decades, experimental and preclinical studies have highlighted the critical roles of histone modifications in cardiovascular development, homeostasis, and diseases. The widely studied histone acetylation is critical in cardiovascular biology and diseases, and inhibitors of histone deacetylases show therapeutic values. In addition to lysine acetylation, a series of novel non-acetyl lysine acylations have recently been recognized. These non-acetyl lysine acylations have been demonstrated to have physiological and pathological functions, and recent studies have analyzed the roles of these non-acetyl lysine acylations in cardiovascular biology. Herein, we review the current advances in the understanding of non-acetyl lysine acylations in cardiovascular biology and discuss open questions and translational perspectives. These new pieces of evidence provide a more extensive insight into the epigenetic mechanisms underlying cardiovascular biology and help assess the feasibility of targeting acylations to treat cardiovascular diseases.

A systematic review and meta-analysis of gut microbiota in diabetic kidney disease: Comparisons with diabetes mellitus, non-diabetic kidney disease, and healthy individuals

BACKGROUND

Gut microbiota has been reported to play an important role in diabetic kidney disease (DKD), however, the alterations of gut bacteria have not been determined.

METHODS

Studies comparing the differences of gut microbiome between patients with DKD and non-DKD individuals using high-throughput sequencing technology, were systematically searched and reviewed. Outcomes were set as gut bacterial diversity, microbial composition, and correlation with clinical parameters of DKD. Qualitative data were summarized and compared through a funnel R script, and quantitative data were estimated by meta-analysis.

RESULTS

A total of 15 studies and 1640 participants were included, the comparisons were conducted between DKD, diabetes mellitus (DM), non-diabetic kidney disease (NDKD), and healthy controls. There were no significant differences of α-diversity between DKD and DM, and between DKD and NDKD, however, significant lower microbial richness was found in DKD compared to healthy controls. Different bacterial compositions were found between DKD and non-DKD subjects. The phylum Actinobacteria were found to be enriched in DKD compared to healthy controls. At the genus level, we found the enrichment of Hungatella, Bilophila, and Escherichia in DKD compared to DM, patients with DKD showed lower abundances of Faecalibacterium compared to those with NDKD. The genera Butyricicoccus, Faecalibacterium, and Lachnospira were depleted in DKD compared to healthy controls, whereas Hungatella, Escherichia, and lactobacillus were significantly enriched. The genus Ruminococcus torques group was demonstrated to be inversely correlated with estimated glomerular filtration rate of DKD.

CONCLUSIONS

Gut bacterial alterations was demonstrated in DKD, characterized by the enrichment of the genera Hungatella and Escherichia, and the depletion of butyrate-producing bacteria, which might be associated with the occurrence and development of DKD. Further studies are still needed to validate these findings, due to substantial heterogeneity.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42022340870.