Changes of gut microbiota in diabetic nephropathy and its effect on the progression of kidney injury.

PURPOSE: We aimed to illustrate gut microbiota and short chain fatty acid (SCFA) levels in diabetic nephropathy (DN) patients, and investigate the mechanism of sodium butyrate in diabetic mellitus (DM) rats. METHODS: Gut microbiota and serum SCFA levels were measured by 16S rDNA and GC-MS. After being built by streptozotocin (DM rats), the DM rats were administered 300 mg/kg sodium butyrate for 12 weeks (DM + BU rats). Gut microbiota, serum and fecal butyrate level were measured. RT-PCR, WB and transmission electron microscopy were performed to explore LC3mRNA or LC3B protein expression, and autophagosomes in kidney tissues. AMPK/mTOR protein expression in renal tissue were also measured. RESULTS: The gut microbial dysbiosis was found in DM and DN groups, and some SCFAs-producing bacteria were decreased in DN group. The serum butyrate concentrations were lower in SCFA-DN group compared with SCFA-HC group and SCFA-DM group in the other cohort. Serum butyrate level was positively correlated with eGFR. Sodium butyrate increased serum and fecal butyrate levels, and improved the enlargement of glomerular area and fibronectin and collagen IV expressions in renal tissues in DM + BU rats. The LC3 mRNA, LC3BII/I ratio and number of autophagosomes were increased in renal tissue of DM + BU rats. Higher p-AMPK/AMPK ratio and lower p-mTOR/ mTOR ratio were shown in renal tissue of DM + BU rats compared with DM rats. CONCLUSIONS: We found the decrease in SCFAs-producing bacteria and low SCFAs concentrations in DN patients. Oral butyrate supplementation may improve kidney injury in DM rats, possibly by increasing autophagy via activating AMPK/mTOR pathway.

l-Arginine and allopurinol supplementation attenuates inflammatory mediators in human osteoblasts-osteoarthritis cells.

This study investigated the synergistic effects of l-arginine and allopurinol on antioxidant and inflammatory mediators in human osteoblasts-osteoarthritis (HOb-OA) cells. The cells were treated with allopurinol (50-150 mg/kg bwt) and l-arginine (50-150 mg/kg bwt) for 72 h. Cell viability, catalase, superoxide dismutase (SOD), glutathione peroxidase (Gpx), reduced glutathione (GSH), lipid peroxidation, and the inflammatory markers interleukin 6 (IL-6), interleukin 1ß (IL-1ß), nuclear factor κB (NF-κB) and tumor necrosis factor alpha (TNF-α) were measured. The combined supplementation with allopurinol and l-arginine increased catalase, SOD, GSH, and Gpx, while it decreased lipid peroxidation, IL-6, IL-1ß, and TNF-α. While TNF-α, IL-6, IL-1ß, and NF-κB mRNA and protein expression were higher in control HOb-OA cells, the combined supplementation with allopurinol and l-arginine substantially reduced their expression in HOb-OA cells by >40%. In summary, combined supplementation with allopurinol and l-arginine might be very effective in osteoarthritis. A search for therapeutic agents that inhibit inflammation could help to prevent and manage osteoarthritis. However, further studies need to determine the biochemical and molecular mechanisms of these agents in osteoarthritis.

[A new nor-sesquiterpene from Cassia occidentalis and its bioactivity].

The phytochemistry investigation on the Cassia occidentalis, a Dai Medicine, was carried out. The C. occidentalis was extracted with ethanol and then partitioned with EtOAc. The EtOAc soluble materials were subjected repeatedly to column chromatography on silica gel and preparative RP-HPLC, leading to isolation of a nor-sesquiterpene, 3-isopropyl-1,6-dimethoxy-5-methyl-naphthalen-7-ol (1), and a sesquiterpene, 2,7-dihydroxy-4-isopropyl-6-methyl-naphthalene-1-carbaldehyde (2). Their structures were determined by means of spectroscopic studies. Compound 1 is a new compound. Compound 2 is also isolated from C. occidentalis for the first time. In addition, the cytotoxicity of compound 1 for NB4, A549, SHSY5Y, PC3, and MCF7 cells line was assayed by using the MTT method, and it displayed potential cytotoxicity for the tested cancer cell-line with IC50 valves of (1.8±0.2), (1.2±0.2), (0.9±0.1), (2.2±0.3), (2.6±0.3) µmol•L⁻¹, respectively.