MicroRNA-195 controls MICU1 expression and tumor growth in ovarian cancer.

MICU1 is a mitochondrial inner membrane protein that inhibits mitochondrial calcium entry; elevated MICU1 expression is characteristic of many cancers, including ovarian cancer. MICU1 induces both glycolysis and chemoresistance and is associated with poor clinical outcomes. However, there are currently no available interventions to normalize aberrant MICU1 expression. Here, we demonstrate that microRNA-195-5p (miR-195) directly targets the 3' UTR of the MICU1 mRNA and represses MICU1 expression. Additionally, miR-195 is under-expressed in ovarian cancer cell lines, and restoring miR-195 expression reestablishes native MICU1 levels and the associated phenotypes. Stable expression of miR-195 in a human xenograft model of ovarian cancer significantly reduces tumor growth, increases tumor doubling times, and enhances overall survival. In conclusion, miR-195 controls MICU1 levels in ovarian cancer and could be exploited to normalize aberrant MICU1 expression, thus reversing both glycolysis and chemoresistance and consequently improving patient outcomes.

Structural characterization, teratogenicity and in vitro avian antimicrobial activity of posterior salivary gland (PSG) toxin from cuttlefish, Sepia prashadi.

A low molecular weight posterior salivary gland (PSG) toxin was isolated and purified from the cuttlefish Sepia prashadi by Reverse Phase High Performance Liquid Chromatography (RP-HPLC). The protein and neutral sugar content of the PSG toxin was determined to be 1.033 mg/g and 282 µg/g. Fourier Transform Infrared (FT-IR) spectroscopy revealed the presence of υ-OH, υ-CO and δ-NH functional groups. Circular Dichroism (CD) spectroscopy and K2D2 analysis quantified the presence of 38.39% α-helix and 9.25% ß-sheet and 52.36% of ß-turn. Matrix Assisted Laser Desorption/Ionization-Time-of Flight/Mass Spectrometry (MALDI-TOF/MS) and MASCOT analysis revealed the amino acid sequence of MEMQSKQQNSKAPANRKIFPWMKTSAVATASKRVEMASLLNLQERQIKIWFQNRMKQKSQQPQTR (1.92 kDa) homologous to homeobox protein H4 of pufferfish, T. rubripes. The PSG toxin showed differential stability with pH and induced premature hatching in Zebrafish eggs and dose dependant developmental malformations in embryos with a Maximum tolerated dose of 1.85 µM. The PSG toxin exhibited significant antibacterial activity with pronounced zone of inhibition against S. typhimurium (12.94 mm) and inhibited avian RBC binding of Newcastle Disease virus (NDV) at a titre value of 1/4. The present study strongly advocates the biomedical potential of the PSG toxin from S. prashadi and illustrates its promise as a potential avian antimicrobial agent of the future.

Low Molecular Weight Sulfated Chitosan: Neuroprotective Effect on Rotenone-Induced In Vitro Parkinson's Disease.

The present investigation was an attempt to study the effect of low molecular weight sulfated chitosan (LMWSC) on in vitro rotenone model of Parkinson's disease (PD) by evaluating cell viability, oxidative stress, mitochondrial membrane potential, DNA fragmentation, and apoptosis. Incubation of SH-SY5Y cells with 100 nm rotenone resulted in neuronal cell death, redox imbalanced mitochondrial dysfunction, DNA fragmentation, condensation, and apoptotic cellular morphology. Rotenone exposure enhanced the expression of preapoptotic (cytochrome C (cyto c), caspase-3, -8, -9, and Bax) and down-regulated the expression of anti-apoptotic (Bcl-2) markers. Reduction of the intracellular reactive oxygen species (ROS) levels ensued due to pretreatment of LMWSC along with consequent normalization of antioxidant enzymes, mitigation of rotenone induced mitochondrial dysfunction and apoptosis. Our current findings suggested that LMWSC exhibit the pronounced neuroprotective effects, which could be due to its antioxidant, mitochondrial protection, and anti-apoptotic properties. We thus conclude that LMWSC could be developed as a novel therapeutic molecule for the benefit of reducing the consequences of PD. However, further extensive preclinical and clinical studies are warranted.

Toxicity, teratogenicity and antibacterial activity of posterior salivary gland (PSG) toxin from the cuttlefish Sepia pharaonis (Ehrenberg, 1831).

Toxins from the posterior salivary gland (PSG) of cuttlefishes are known toxins with pronounced toxicity. In the present study, ionic peptide rich PSG toxin from the cuttlefish S. pharaonis was isolated by ion exchange chromatography and purified by Reversed Phase High Performance Liquid Chromatography (RP-HPLC), with active fraction at a retention time of 26min. The net protein content of the PSG toxin was estimated to be 46.6mg at a proximate molecular weight of∼50kDa. Fourier Transform Infrared Spectroscopy (FT-IR) of PSG toxin revealed the presence of alcoholic OH, primary NH, alkyl CH and conjugated CONH functional groups. Circular Dichroism (CD) spectroscopy and K2D analysis of the PSG toxin confirmed the presence of secondary structure with 36.77% α-helix,12.31% ß sheet and 50.92% random coil. Scanning Electron Microscopy (SEM) of the PSG toxin eluted amberlite IRA 900 Cl- resin showed surface abrasion and corrosive blebbing. Energy Dispersive X-ray Spectrometry (EDX) analysis of PSG toxin treated resin revealed increase in nitrogen and sulphur content corresponding to amino acid composition. Teratogenicity of PSG toxin against Zebrafish embryo demonstrated developmental malformations and premature hatching at a maximum tolerated dose of 1.25µM. The PSG toxin (50µM) exhibited commendable inhibitory activity with pronounced zone of inhibition against gram E. coli (10mm) and K. pneumonia (10mm). The results strongly demonstrate the toxicity of the ionic peptide rich PSG toxin from S. pharaonis and its exploitation for its promise as a potential antibacterial agent of the future.

Data supporting the anticancer activity of posterior salivary gland (PSG) toxin from the cuttlefish Sepia pharaonis Ehrenberg (1831).

The data presented illustrated the in vitro anti-proliferative effect of the PSG toxin from the cuttlefish, Sepia pharaonis. The cytostatic potentials of the PSG toxin were determined by the lymphocyte migration inhibition assay. The PSG toxin (50 µg/ml) exhibited commendable inhibition of the migration of lymphocytes across the agarose gel matrix under the presence of lipopolysaccharide mitogen, with a mean migration index of 0.625. The cytotoxicity of the PSG toxin against selected cancer cell lines was determined using the MTT assay. The PSG toxin exhibited dose-dependent cytotoxicity against the MCF-7 breast cancer cells followed by KB (oral), HeLa (cervical) and A549 (lung) cancer cell lines. The PSG toxin also exhibited proportional release of LDH leakage by mitochondrial damage with an IC50 of 13.85 µM against MCF-7 breast cancer cells. The in vitro anticancer activity of the PSG toxin against the selected cell lines was evaluated by Karthik et al. (2017) [1].

In vitro and in vivo anticancer activity of posterior salivary gland toxin from the cuttlefish Sepia pharaonis, Ehrenberg (1831).

Posterior salivary gland (PSG) toxins are high molecular weight toxins secreted by cephalopods and gastropods which possess immense potentials in biomedical applications. In the present study, the biomedical potentials of the PSG toxin from the cuttlefish, S. pharaonis was determined in vitro and in vivo. The cytostatic potentials of the PSG toxin was determined by the lymphocyte migration inhibition assay. The PSG toxin (50 µg/ml) effectively inhibited the migration of lymphocytes across the agarose gel matrix under the presence of lipopolysaccharide mitogen. The cytotoxicity of the PSG toxin against cancer cell lines was determined using the MTT assay. The PSG toxin exhibited highest cytotoxicity against the MCF-7 breast cancer cells (IC50-10.64 µM) followed by KB, HeLa and A549 cells. The PSG toxin also exhibited proportional release of LDH leakage by mitochondrial damage with an IC50-13.85 µM against MCF-7 breast cancer cells. Flow cytometry analysis revealed that the PSG toxin induced apoptosis in MCF-7 cells by cell cycle arrest at G0/G1 phase. The PSG toxin (80 mg/kg b.w.) exhibited pronounced reduction (29%) in tumor growth in experimentally induced breast carcinoma in female Balb/C mice, in vivo. Hematological analysis illustrated the restoration of blood and biochemical parameters by the PSG toxin in mice induced with tumor. Histopathology studies also revealed the restitution of morphological features in the mammary tumor and vital organs in mice treated with the PSG toxin without any observed toxicity and adverse effects. The PSG toxin further exhibited commendable potentials in the prevention of tumor metastasis into immediate organs viz lungs, thus functioning as an anti-metastatic agent. The results of the present study showed that the PSG toxin exhibited immense promise as a potential peptide based anticancer agent, in future.

Structural characterization and in vitro biomedical activities of sulfated chitosan from Sepia pharaonis.

A low molecular weight sulfated chitosan (SP-LMWSC) was isolated from the cuttlebone of Sepia pharaonis. Elemental analysis established the presence of C, H and N. The sulfation of SP-LMWSC was confirmed by the presence of characteristic peaks in FT-IR and FT-Raman spectra. The thermal properties of SP-LMWSC were studied by thermogravimetric analysis and differential scanning calorimetry. Electrolytic conductivity of SP-LMWSC was measured by cyclic voltammetry and the molecular weight was determined by MALDI-TOF/MS. The molecular structure and sulfation sites of SP-LMWSC were unambiguously confirmed using (1)H, (13)C, 2D COSY and 2D HSQC NMR spectroscopy. SP-LMWSC exhibited increased anticoagulant activity in avian blood by delaying coagulation parameters and displayed cytostatic activity by inhibiting the migration of avian leucocytes. SP-LMWSC demonstrated avian antiviral activity by binding to Newcastle disease virus receptors at a low titer value of 1/64. These findings suggested that SP-LMWSC isolated from an industrial discard holds immense potentials as carbohydrate based pharmaceuticals in future.