Formononetin improves the inflammatory response and bone destruction in knee joint lesions by regulating the NF-kB and MAPK signaling pathways.

Formononetin (FMN) is a phytoestrogen that belongs to the isoflavone family. It has antioxidant and anti-inflammatory effects, as well as, many other biological activities. Existing evidence has aroused interest in its ability to protect against osteoarthritis (OA) and promote bone remodeling. To date, research on this topic has not been thorough and many issues remain controversial. Therefore, the purpose of our study was to explore the protective effect of FMN against knee injury and clarify the possible molecular mechanisms. We found that FMN inhibited osteoclast formation induced by receptor activator of NF-κB ligand (RANKL). Inhibition of the phosphorylation and nuclear translocation of p65 in the NF-κB signaling pathway plays a role in this effect. Similarly, during the inflammatory response of primary knee cartilage cells activated by IL-1ß, FMN inhibited the NF-κB signaling pathway and the phosphorylation of the ERK and JNK proteins in the MAPK signaling pathway to suppress the inflammatory response. In addition, in vivo experiments showed that both low- and high-dose FMN had a clear protective effect against knee injury in the DMM (destabilization of the medial meniscus) model, and the therapeutic effect of high-dose FMN was stronger. In conclusion, these studies provide evidence of the protective effect of FMN against knee injury.

The group III two-component histidine kinase AlHK1 is involved in fungicides resistance, osmosensitivity, spore production and impacts negatively pathogenicity in Alternaria longipes.

Members of group III histidine kinases from different filamentous fungi were previously shown to mediate osmoregulation and resistance to dicarboximide, phenylpyrrole and, aromatic hydrocarbon fungicides. In this study, we report the disruption of the gene encoding group III histidine kinase, AlHK1, in the economically important plant pathogen Alternaria longipes. The AlHK1 gene disruption had pleiotropic effects on this fungus. Besides the expected osmosensitivity and fungicides resistance, AlHK1 participated in the spore production process. In addition, the ΔAlHK1 strains had stronger aggressive ability to infect their host plant than that of their parental strain, the wild-type strain C-00, suggested that AlHK1 was involved in the pathogenicity of A. longipes and performed in this function by a negative manner. This is the first report to our knowledge.

Isolation of talathermophilins from the thermophilic fungus Talaromyces thermophilus YM3-4.

Six indole alkaloids with various levels of prenylation were isolated from the thermophilic fungus Talaromyces thermophilus strain YM3-4. Their structures were identified by NMR and MS spectroscopic analyses. Compounds 1 and 2 are new analogues of the key versatile precursor notoamide E. Compound 3 is a novel analogue of preechinulin, and compound 4 was reported as a natural occurring cyclo(glycyltryptophyl) for the first time. The metabolite profile of this thermophilic organism displayed a biosynthetic pathway for talathermophilins.

Anoxybacillus tengchongensis sp. nov. and Anoxybacillus eryuanensis sp. nov., facultatively anaerobic, alkalitolerant bacteria from hot springs.

Two novel thermophilic, spore-forming bacterial strains, T-11(T) and E-112(T), were isolated from hot springs in Tengchong and Eryuan counties of Yunnan province in south-west China. The strains were Gram-stain-positive rods, occurring singly or in chains. Growth of strain T-11(T) was observed between 30 and 75 °C (optimum 50 °C) and at pH 7-11 (optimum pH 8.5), while the temperature range for strain E-112(T) was 35-70 °C (optimum 55 °C) and the pH range was 7.0-11.0 (optimum pH 8.0). The DNA G+C contents of strains T-11(T) and E-112(T) were 41.1 and 42.6 mol%, respectively. On the basis of 16S rRNA gene sequence similarity, the two strains were shown to be related most closely to Anoxybacillus species. The chemotaxonomic characteristics [predominant isoprenoid quinone menaquinone 7 (MK-7); major fatty acids iso-C(15 : 0) and iso-C(17 : 0)] also supported the affiliation of strains T-11(T) and E-112(T) to the genus Anoxybacillus. The results of DNA-DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strains T-11(T) and E-112(T) from Anoxybacillus species with validly published names. Strains T-11(T) and E-112(T) therefore represent two novel species, for which the names Anoxybacillus tengchongensis sp. nov. (type strain T-11(T) =CCTCC AB209237(T) =KCTC 13721(T)) and Anoxybacillus eryuanensis sp. nov. (type strain E-112(T) =CCTCC AB209236(T) =KCTC 13720(T)) are proposed.

Isolation of putative biosynthetic intermediates of prenylated indole alkaloids from a thermophilic fungus Talaromyces thermophilus.

The putative key biosynthetic intermediates of prenylated indole alkaloids have long been proposed but never isolated. Two such alkaloids, named talathermophilins A and B (1 and 2), were isolated from a thermophilic fungus Talaromyces thermophilus strain YM1-3 and were identified by NMR and MS spectroscopic analyses. The ratio of 1 and 2 in the culture broths was unexpectedly rather constant (about 2:3), which even remained unchanged despite the addition of exogenous 1 or 2, suggesting that talathermophilins might be of special function for the extremophilic fungus.

Diversity of thermophilic fungi in Tengchong Rehai National Park revealed by ITS nucleotide sequence analyses.

The geothermal sites near neutral and alkalescent thermal springs in Tengchong Rehai National Park were examined through cultivation-dependent approach to determine the diversity of thermophilic fungi in these environments. Here, we collected soils samples in this area, plated on agar media conducive for fungal growth, obtained pure cultures, and then employed the method of internal transcribed spacer (ITS) sequencing combined with morphological analysis for identification of thermophilic fungi to the species level. In total, 102 strains were isolated and identified as Rhizomucor miehei, Chaetomium sp., Talaromyces thermophilus, Talaromyces byssochlamydoides, Thermoascus aurantiacus Miehe var. levisporus, Thermomyces lanuginosus, Scytalidium thermophilum, Malbranchea flava, Myceliophthora sp. 1, Myceliophthora sp. 2, Myceliophthora sp. 3, and Coprinopsis sp. Two species, T. lanuginosus and S. thermophilum were the dominant species, representing 34.78% and 28.26% of the sample, respectively. Our results indicated a greater diversity of thermophilic fungi in neutral and alkaline geothermal sites than acidic sites around hot springs reported in previous studies. Most of our strains thrived at alkaline growth conditions.