Background: Hormone-refractory prostate cancer (HRPC) is characterized by poor response to chemotherapy and high mortality, particularly among African American men when compared to other racial/ethnic groups. It is generally accepted that docetaxel, the standard of care for chemotherapy of HRPC, primarily exerts tumor cell death by inducing mitotic catastrophe and caspase-dependent apoptosis following inhibition of microtubule depolymerization. However, there is a gap in our knowledge of mechanistic events underlying docetaxel-induced caspaseindependent cell death, and the genes that antagonize this process. This knowledge is important for circumventing HRPC chemoresistance and reducing disparities in prostate cancer mortality.

Lipotoxicity involves a series of pathological cellular responses after exposure to elevated levels of fatty acids. This process may be detrimental to normal cellular homeostasis and cell viability. The present study shows that nerve growth factor-differentiated PC12 cells (NGFDPC12) and rat cortical cells (RCC) exposed to high levels of palmitic acid (PA) exhibit significant lipotoxicity and death linked to an “augmented state of cellular oxidative stress” (ASCOS). The ASCOS response includes generation of reactive oxygen species (ROS), alterations in the mitochondrial transmembrane potential, and increase in the mRNA levels of key cell death/survival regulatory genes. The observed cell death was apoptotic based on nuclear morphology, caspase-3 activation, and cleavage of lamin B and PARP. Quantitative real-time PCR measurements showed that cells undergoing lipotoxicity exhibited an increase in the expression of the mRNAs encoding the cell death-associated proteins BNIP3 and FAS receptor. Cotreatment of NGFDPC12 and RCC cells undergoing lipotoxicity with docosahexaenoic acid (DHA) and bovine serum albumin (BSA) significantly reduced cell death within the first 2 hr following the initial exposure to PA. The data suggest that lipotoxicity in NGFDPC12 and cortical neurons triggers a strong cell death apoptotic response. Results with NGFDPC12 cells suggest a linkage between induction of ASCOS and the apoptotic process and exhibit a temporal window that is sensitive to DHA and BSA interventions.

There is increasing evidence that an augmented state of cellular oxidative stress modulates the expression of stress genes implicated in diseases associated with health disparities such as certain cancers and diabetes. Lens epithelium -derived growth factor p75 (LEDGF/ p75), also known as DFS70 autoantigen, is emerging as a survival oncoprotein that promotes resistance to oxidative stress -induced cell death and chemotherapy. We previously showed that LEDGF/p75 is targeted by autoantibodies in prostate cancer patients and is overexpressed in prostate tumors, and that its stress survival activity is abrogated during apoptosis. LEDGF/ p75 has a COOH-terminally truncated splice variant, p52, whose role in stress survival and apoptosis has not been thoroughly investigated. We observed unbalanced expression of these proteins in a panel of tumor cell lines, with LEDGF/p75 generally expressed at higher levels. During apoptosis, caspase-3 cleaved p52 to generate a p38 fragment that lacked the NH 2 -terminal PWWP domain and failed to transactivate the Hsp27 promoter in reporter assays. However, p38 retained chromatin association properties and repressed the transactivation potential of LEDGF/p75. Overexpression of p52 or its variants with truncated PWWP domains in several tumor cell lines induced apoptosis, an activity that was linked to the presence of an intron-derived COOH-terminal sequence. These results implicate the PWWP domain of p52 in transcription function but not in chromatin association and proapoptotic activities. Consistent with their unbalanced expression in tumor cells, LEDGF/p75 and p52 seem to play antagonistic roles in the cellular stress response and could serve as targets for novel antitumor therapies.

Global health agencies estimate an increase of chronic diseases in South America. Nevertheless, few studies have investigated chronic diseases and their risk factors in the perspective of multimorbidity. This research aimed to identify these aspects in a primary health care setting of central Argentina. The Pan America version of the STEP wise approach surveillance (STEPS) instrument of the World Health Organization was applied to 1044 participants, 365 men and 679 women, with a mean age of 43 years. High prevalence of overweight (33.5%), obesity (35.2%), central obesity (54%), dyslipidemia (43.5%), metabolic syndrome (21.1%), low intake of fruit and vegetables (91.8%), low levels of physical activity (71.5%), risky alcohol consumption (28%), and smoking (22.5%) were detected. Hypertension and diabetes were the most prevalent chronic conditions and the total prevalence of multimorbidity was 33.1%, with 2, 3, 4, 5 and 6 chronic conditions found in 19.9%, 9.1%, 2.6%, 1.1% and 0.4% of the population, respectively. Multimorbidity affected 6.4% of the young, 31.7% of the adults, and 60.6% of the elderly, and was more prevalent among women, and in participants with lower levels of education. Having multimorbidity was significantly associated with obesity, central obesity, and higher concentrations of total blood cholesterol, low-density lipoprotein cholesterol, triglycerides, and glucose. A website was made available to the participants in order to share the experimental results and health-promoting information.

This study aimed to evaluate changes in dietary and lifestyle habits during the period of confinement due to the first wave of the COVID-19 pandemic in Ibero-American countries. A cross-sectional investigation was conducted with 6,325 participants of both genders (68% women), over 18 years of age and from five countries: Brazil (N = 2,171), Argentina (N = 1,111), Peru (N = 1,174), Mexico (N = 686), and Spain (N = 1,183). Data were collected during the year 2020, between April 01 and June 30 in Spain and between July 13 and September 26, in the other countries studied using a self-administered online survey designed for the assessment of sociodemographic, employment, physical activity, health status, and dietary habits changes. Most participants (61.6%), mainly those from Spain, remained constant, without improving or worsening their pattern of food consumption. Among those who changed, a pattern of better eating choices prevailed (22.7%) in comparison with those who changed toward less healthy choices (15.7%). Argentina and Brazil showed the highest proportion of changes toward a healthier pattern of food consumption. Peruvians and Mexicans were less likely to make healthy changes in food consumption (OR: 0.51; 95% CI: 0.4–0.6 and OR: 0.69; 95% CI: 0.4–0.8, respectively), when compared to Argentinians. Most respondents did not change their pattern of meal consumption, but those who did reduced their consumption of main meals and increased intake of small meals and snacks. Although most participants affirmed to be doing physical activity at home, about one-half reported perception of weight gain. Individuals with alterations in sleep pattern (either by increasing or decreasing sleep time) were more likely to change their diets to a healthier pattern. In contrast, individuals with confirmed diagnosis of COVID-19 and those who reported feeling anxious were more likely to perform changes to a less healthy eating pattern (OR: 1.72; 95% CI: 1.2–2.3 and OR: 1.21; 95% CI: 1.1–1.4, respectively). In conclusion, although most participants remained constant in their eating habits, lifestyle changes and anxiety feelings were reported. Among those who changed patterns of food consumption, healthier choices prevailed, with differences between countries. However, there were alterations in the distribution of meals, with higher consumption of snacks and small meals. These results can be used to guide policies to prevent deleterious consequences that may affect the incidence of chronic diseases.

Lipotoxicity, which is triggered when cells are exposed to elevated levels of free fatty acids, involves cell dysfunction and apoptosis and is emerging as an underlying factor contributing to various pathological conditions including disorders of the central nervous system and diabetes. We have shown that palmitic acid (PA)-induced lipotoxicity (PA-LTx) in nerve growth factor-differentiated PC12 (NGFDPC12) cells is linked to an augmented state of cellular oxidative stress (ASCOS) and apoptosis, and that these events are inhibited by docosahexanoic acid (DHA). The mechanisms of PA-LTx in nerve cells are not well understood, but our previous findings indicate that it involves ROS generation, mitochondrial membrane permeabilization (MMP), and caspase activation. The present study used nerve growth factor differentiated PC12 cells (NGFDPC12 cells) and found that lysosomal membrane permeabilization (LMP) is an early event during PA-induced lipotoxicity that precedes MMP and apoptosis. Cathepsin L, but not cathepsin B, is an important contributor in this process since its pharmacological inhibition significantly attenuated LMP, MMP, and apoptosis. In addition, co-treatment of NGFDPC12 cells undergoing lipotoxicity with DHA significantly reduced LMP, suggesting that DHA acts by antagonizing upstream signals leading to lysosomal dysfunction. These results suggest that LMP is a key early mediator of lipotoxicity, and underscore the value of interventions targeting upstream signals leading to LMP for the treatment of pathological conditions associated with lipotoxicity.

Objective. Autoantibodies to DNA topoisomerase I (topo I) are associated with diffuse systemic sclerosis (SSc), appear to be antigen driven, and may be triggered by cryptic epitopes exposed during in vivo topo I fragmentation. These autoantibodies recognize topo I and fragments of this autoantigen generated during apoptosis and necrosis. We undertook this study to determine whether lysosomal cathepsins are involved in topo I fragmentation during necrosis.Methods. Topo I cleavage during necrosis was assessed by immunoblotting of lysates from L929 fibroblasts exposed to tumor necrosis factor ␣ (

Objective It was previously reported that docosahexanoic acid (DHA) reduces TNF-α-induced necrosis in L929 cells. However, the mechanisms underlying this reduction have not been investigated. The present study was designed to investigate cellular and biochemical mechanisms underlying the attenuation of TNF-α-induced necroptosis by DHA in L929 cells. Methods L929 cells were pre-treated with DHA prior to exposure to TNF-α, zVAD, or Necrostatin-1 (Nec-1). Cell death and survival were assessed by MTT and caspase activity assays, and microscopic visualization. Reactive oxygen species (ROS) were measured by flow cytometry. C16- and C18-ceramide were measured by mass spectrometry. Lysosomal membrane permeabilization (LMP) was evaluated by fluorescence microscopy and flow cytometry using Acridine Orange. Cathepsin L activation was evaluated by immunoblotting and fluorescence microscopy. Autophagy was assessed by immunoblotting of LC3-II and Beclin. Results Exposure of L929 cells to TNF-α alone for 24 h induced necroptosis, as evidenced by inhibition of cell death by Nec-1, absence of caspase-3 activity and lamin B cleavage, and morphological analysis. DHA attenuated multiple biochemical events associated with TNF-α-induced necroptosis, including ROS generation, ceramide production, lysosomal dysfunction, cathepsin L activation, and autophagic features. DHA also attenuated zVAD-induced necroptosis but did not attenuate the enhanced apoptosis and necrosis induced by combination of TNF-α with Actinomycin D or zVAD, respectively, suggesting that its protective effects might be limited by the strength of the cell death insult induced by TNF-α. Conclusions DHA effectively attenuates TNF-α-induced necroptosis and autophagy, most likely via its ability to inhibit TNF-α-induced sphingolipid metabolism and oxidative stress. These results highlight the role of this Omega-3 fatty acid in antagonizing inflammatory cell death.