RIPK1 kinase activity has been shown to be essential to driving pyroptosis, apoptosis, and necroptosis. However, here we show a kinase activity–independent role for RIPK1 in these processes using a model of TLR priming in a TAK1-deficient setting to mimic pathogen-induced priming and inhibition. TLR priming of TAK1-deficient macrophages triggered inflammasome activation, including the activation of caspase-8 and gasdermin D, and the recruitment of NLRP3 and ASC into a novel RIPK1 kinase activity–independent cell death complex to drive pyroptosis and apoptosis. Furthermore, we found fully functional RIPK1 kinase activity–independent necroptosis driven by the RIPK3–MLKL pathway in TAK1-deficient macrophages. In vivo, TAK1 inactivation resulted in RIPK3–caspase-8 signaling axis–driven myeloid proliferation and a severe sepsis-like syndrome. Overall, our study highlights a previously unknown mechanism for RIPK1 kinase activity–independent inflammasome activation and pyroptosis, apoptosis, and necroptosis (PANoptosis) that could be targeted for treatment of TAK1-associated myeloid proliferation and sepsis.

Serum protein profiles of patients with bacterial sepsis from the day of diagnosis until recovery/mortality were compared from early to late stages in response to severe sepsis using two dimensional electrophoresis. The proteins exhibiting changes during the course of sepsis (20‑28 day mortality) were selected and identified by matrix‑assisted laser desorption ionization‑time of flight‑tandem mass spectrometry. Among the proteins identified, haptoglobin (Hp), transthyretin (TTR), orosomucoid 1/α1 acid glycoprotein (ORM1), α1 antitrypsin (A1AT), serum amyloid A (SAA) and S100A9 exhibited differential expression patterns between survivors (S; n=6) and non‑survivors (NS; n=6), particularly during the early stages of sepsis. Expression factors (EFs), taken as the ratio between the NS and S during early stages, showed ratios of Hp, 0.39 (P≤0.012); TTR, 3.96 (P≤0.03); ORM1, 0.69 (P≤0.79); A1AT, 0.92 (P≤0.87) and SAA, 0.69 (P≤0.01). S100A9, an acute phase protein, exhibited an EF ratio of 1.68 (P≤0.004) during the end stages of sepsis. A delayed rise in levels was observed in Hp, A1AT, ORM1, S100A9 and SAA, whereas TTR levels increased during the early stages of sepsis in NS. Analysis of inflammatory responses in the early stages of sepsis revealed increased mRNA expression in leukocytes of interleukin (IL)‑6 (EF, 2.50), IL‑10 (EF, 1.70) and prepronociceptin (EF, 1.6), which is a precursor for nociceptin in NS compared with S, and higher Toll‑like receptor‑4 (EF, 0.30) levels in S compared with NS. Therefore, a weaker acute phase response in the early stages of sepsis in NS, combined with an inefficient inflammatory response, may contribute to sepsis mortality.

Purpose: Selenium nanoparticles (SeNP) have several applications in the field of biotechnology, including their use as anti-cancer drugs. The purpose of the present study is to analyze the efficacy of green synthesis on the preparation of SeNP and its effect on their anti-cancer properties. Methods: A bacterial strain isolated from a freshwater source was shown to efficiently synthesize SeNP with potential therapeutic properties. The quality and stability of the NP were studied by scanning electron microscopy, X-ray diffraction, zeta-potential and FTIR analysis. A cost-effective medium formulation from biowaste having 6% banana peel extract enriched with 0.25 mM tryptophan was used to synthesize the NP. The NP after optimization was used to analyze their anti-tumor and anti-angiogenic activity. For this purpose, first, the cytotoxicity of the NP against cancer cells was analyzed by MTT assay and then chorioallantoic membrane assay was performed to assess anti-angiogenic activity. Further, cell migration assay and clonogenic inhibition assay were performed to test the anti-tumor properties of SeNP. To assess the cytotoxicity of SeNP on healthy RBC, hemolysis assay was performed. Results: The strain identified as Pseudomonas stutzeri (MH191156) produced phenazine carboxylic acid, which aids the conversion of Se oxyanions to reduced NP state, resulting in particles in the size range of 75 nm to 200 nm with improved stability and quality of SeNP, as observed by zeta (ξ) potential of the particles which was found to be −46.2 mV. Cytotoxicity of the SeNP was observed even at low concentrations such as 5 µg/mL against cervical cancer cell line, ie, HeLa cells. Further, neovascularization was inhibited by upto 30 % in CAMs of eggs coinoculated with SeNp when compared with untreated controls, indicating significant anti-angiogenic activity of SeNP. The NP also inhibited the invasiveness of HeLa cells as observed by decreased cell migration and clonogenic proliferation. These observations indicate significant anti-tumor and anti-angiogenic activity of the SeNP in cervical cancer cells. Conclusion: P. stutzeri (MH191156) is an efficient source of Se NP production with potential anti-angiogenic and anti-tumor properties, particularly against cervical cancer cells.

Phosphatidylethanolamine-binding protein is crucial in regulation of MAPK and PKC pathways. Its diverse roles, including regulating these pathways keep cell differentiation and proliferation in check. This review outlines some latest findings which greatly add to our current knowledge of phosphatidylethanolamine-binding protein.

The present study reveals the production of dark, extracellular melanin pigment (386 mg/L) on peptone yeast extract iron agar medium by Streptomyces puniceus RHPR9 using the gravimetric method. UV-Visible, Fourier Transform Infrared (FTIR), and Nuclear Magnetic Resonance (1H) (NMR) spectroscopy confirmed the presence of melanin. Extracted melanin showed antibacterial activity against human pathogens such as Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli except for Klebsiella pneumoniae. A potent free radical scavenging activity was observed at 100 μg/mL of melanin by the DPPH method with a concentration of 89.01±0.05% compared with ascorbic acid 96.16±0.01%. Antitumor activity of melanin was evaluated by MTT assay against HEK 293, HeLa, and SK-MEL-28 cell lines with IC50 values of 64.11±0.00, 14.43±0.02, and 13.31±0.01 μg/mL respectively. Melanin showed maximum anti-inflammatory activity with human red blood cells (hRBC) (78.63 ± 0.01%) and minimum hemolysis of 21.37±0.2%. The wound healing potential of the pigment was confirmed on HeLa cells, cell migration was calculated, and it was observed that cell migration efficiency decreased with an increase in the concentration of melanin. To our knowledge, this is the first evidence of melanin produced from S. puniceus RHPR9 that exhibited profound scavenging, anti-inflammatory and cytotoxic activities.