Diversity, Antimicrobial, Antioxidant, and Anticancer Activity of Culturable Fungal Endophyte Communities in Cordia dichotoma.

Endophytic fungi are a significant source of secondary metabolites, which are chemical compounds with biological activities. The present study emphasizes the first-time isolation and identification of such fungi and their pharmacological activities from the medicinal plant Cordia dichotoma, which is native to Jammu, India. The Shannon Wiener diversity index revealed a wide range of fungal endophytes in root (1.992), stem (1.645), and leaf (1.46) tissues. A total of 19 endophytic fungi belonging to nine different genera were isolated from this plant and the majority belonged to the Ascomycota phylum. ITS rRNA gene sequencing was used to identify the fungal strains and they were submitted in NCBI GenBank. The most potent fungal isolate Cladosporium cladosporioides OP870014 had strong antimicrobial, antioxidant, and anticancer activity against MCF-7, HCT-116, and PC-3 cancer cell lines. The LC-MS and GC-MS analyses of the ethyl acetate extract of C. cladosporioides were examined to identify the bioactive metabolites. The major compounds of the crude extract derived from C. cladosporioides OP870014, according to GC-MS, are spiculisporic acid; dibutyl phthalate; phenylethyl alcohol; cyclohexanone, 2,3,3-trimethyl-2-3-methylbutyl; pyrrolo[1,2-a]pyrazine-1,4-dione,hexahydro-3-(phenylmethyl);2,5-piperazinedione,3,6-bis(2-methylpropyl); and heneicosane which possessed antimicrobial, anticancerous, and antioxidant activities. The findings revealed that C. dichotoma has the capacity to host a wide variety of fungal endophytes and that secondary metabolites from the endophytic fungus may be a source of alternative naturally occurring antimicrobial, antioxidant, and cytotoxic compounds.

Rottlerin renders a selective and highly potent CYP2C8 inhibition to impede EET formation for implication in cancer therapy.

CYP2C8 is a crucial CYP isoform responsible for the metabolism of xenobiotics and endogenous molecules. CYP2C8 converts arachidonic acid to epoxyeicosatrienoic acids (EETs) that cause cancer progression. Rottlerin possess significant anticancer actions. However, information on its CYP inhibitory action is lacking in the literature and therefore, we aimed to explore the same using in silico, in vitro, and in vivo approaches. Rottlerin showed highly potent and selective CYP2C8 inhibition (IC50 < 0.1 µM) compared to negligible inhibition (IC50 > 10 µM) for seven other experimental CYPs in human liver microsomes (HLM) (in vitro) using USFDA recommended index reactions. Mechanistic studies reveal that rottlerin could reversibly (mixed-type) block CYP2C8. Molecular docking (in silico) results indicate a strong interaction could occur between rottlerin and the active site of human CYP2C8. Rottlerin boosted the plasma exposure of repaglinide and paclitaxel (CYP2C8 substrates) by delaying their metabolism using the rat model (in vivo). Multiple-dose treatment of rottlerin with CYP2C8 substrates lowered the CYP2C8 protein expression and up-regulated & down-regulated the mRNA for CYP2C12 & CYP2C11 (rat homologs), respectively, in rat liver tissue. Rottlerin substantially hindered the EET formation in HLM. Overall results of rottlerin on CYP2C8 inhibition and EET formation insinuate further exploration for cancer therapy.

Rottlerin promotes anti-metastatic events by ameliorating pharmacological parameters of paclitaxel: An in-vivo investigation in the orthotopic mouse model of breast cancer.

Despite substantial breakthroughs in cancer research, there is hardly any specific therapy available to date that can alleviate triple-negative breast cancer (TNBC). Paclitaxel is the first-line chemotherapy option, but its treatment is often associated with early discontinuation of therapy due to the development of resistance and/or precipitation of severe side effects. In the quest to establish a suitable combination therapy with a low dose of paclitaxel, we explored rottlerin (a pure and characterized phytoconstituent from Mallotus philippensis) because of its multifaceted pharmacological actions against cancer. The study was performed to assess the therapeutic effects of rottlerin (5-20 mg/kg) with a low dose of paclitaxel (5 mg/kg) using a highly aggressive mouse mammary carcinoma model. Rottlerin augmented the paclitaxel effect by reducing tumor burden as well as metastatic lung nodules formation. Rottlerin in combination with paclitaxel remarkably altered the expression of vital epithelial-mesenchymal transition (EMT) markers such as E-cadherin, Snail 1, & Vimentin and thus improved the anti-metastatic efficacy of paclitaxel. Significant attenuation of anti-apoptotic protein (Bcl-2) along with amplification of pro-apoptotic (cleaved PARP) marker confers that rottlerin could ameliorate the pro-apoptotic potential of paclitaxel. In this study, a rational combination of rottlerin and paclitaxel treatment curtailed CYP2J2 expression and epoxyeicosatrienoic acids (EETs) levels, responsible for restrain tumor growth and metastasis. Additionally, rottlerin lessened paclitaxel treatment-mediated hematological alterations and prevented paclitaxel treatment-linked key serum biochemical changes related to organ toxicities. These rottlerin treatment-mediated protective changes are closely associated with the lower paclitaxel accumulation in the corresponding tissues. Rottlerin caused significant pharmacokinetic interaction with paclitaxel to boost the plasma level of paclitaxel in a typical mouse model and possibly helpful towards the use of a low dose of paclitaxel in combination. Overall, it can be stated that rottlerin has significant potential to augment the anti-metastatic efficacy of paclitaxel via impeding EMT activation along with attenuating its treatment-associated toxicological alterations. Hence, rottlerin has significant potential to explore further as a suitable neoadjuvant therapy with paclitaxel against TNBC.