Natural products from anaerobes

Journal of Industrial Microbiology & Biotechnology - Natural product discovery in the microbial world has historically been biased toward aerobes. Recent in silico analysis demonstrates that...     

Development of hydroxamate-based histone deacetylase inhibitors containing 1,2,4-oxadiazole moiety core with antitumor activities

Histone deacetylases (HDACs) has proved to be promising target for the development of antitumor drugs. In this study, we reported the design and synthesis of a class of novel hydroxamate-based bis-substituted aromatic amide HDAC inhibitors with 1,2,4-oxadiazole core. Most newly synthesized compounds displayed excellent HDAC1 inhibitory effects and significant anti-proliferative activities. Among them, compounds 11a and 11c increased acetylation of histone H3 and H4 in dose-dependent manner. Furthermore, 11a and 11c remarkably induced apoptosis in HepG2 cancer cells. Finally, the high potency of compound 11a was rationalized by molecular docking studies.     

Seco-4-methyl-DCK derivatives as potent chemosensitizers

Twenty-five seco-4-methyl-DCK derivatives were designed, synthesized and evaluated for chemoreversal activity when combined with paclitaxel or vincristine in two drug-resistant cancer cell lines (A2780/T and KB-V) respectively. Most of the new compounds displayed moderate to significant MDR reversal activities in the P-gp overexpressing A2780/T and KB-V cells. Especially, compounds 7o and 7y showed the most potent chemosensitization activities with more than 496 and 735 reversal ratios at a concentration of 10?μM. Unexpectedly the newly synthesized compounds did not show chemosensitization activities observed in a non-P-gp overexpressing cisplatin resistant human ovarian cancer cell line (A2780/CDDP), implying that the MDR reversal effects might be associated with P-gp overexpression. Moreover, these compounds did not exhibit significant antiproliferative activities against nontumorigenic cell lines (HUVEC, HOSEC and T29) compared to the positive control verapamil at the tested concentration, which suggested better safety than verapamil. The pharmacological actions of the compounds will be studied further to explore their merit for development as novel candidates to overcome P-gp mediated MDR cancer.     

Emerging roles of long non‐coding RNAs in neuropathic pain

Neuropathic pain, a type of chronic and potentially disabling pain resulting from primary injury/dysfunction of the somatosensory nervous system and spinal cord injury, is one of the most intense types of chronic pain, which incurs a significant economic and public health burden. However, our understanding of its cellular and molecular pathogenesis is still far from complete. Long non‐coding RNAs (lncRNAs) are important regulators of gene expression and have recently been characterized as key modulators of neuronal functions. Emerging evidence suggested that lncRNAs are deregulated and play pivotal roles in the development of neuropathic pain. This review summarizes the current knowledge about the roles of deregulated lncRNAs (eg, KCNA2‐AS, uc.48+, NONRATT021972, MRAK009713, XIST, CCAT1) in the development of neuropathic pain. These studies suggested that specific regulation of lncRNAs or their downstream targets might provide novel therapeutic avenues for this refractory disease.     

Cyclic tripeptide-based potent human SIRT7 inhibitors

In the current study, two cyclic tripeptides respectively harboring a thiourea-type and a carboxamide-type of catalytic mechanism-based sirtuin inhibitory warheads as the central residue were found to behave as potent (low μM level) inhibitors against the tRNA-activated human SIRT7 deacetylase activity. Despite exhibiting a potent pan-inhibition against the deacylase activities of the five tested human sirtuins (i.e. SIRT1/2/3/6/7), these two compounds represent the first examples of potent SIRT7 inhibitors ever identified thus far, and their identification could facilitate the future development of more potent and selective SIRT7 inhibitors.