Are lipid disorders involved in the predominance of human T-lymphotropic virus-1 infections in women?

Oncogenic viruses and host lipid metabolism: a new perspective

As noncellular organisms, viruses do not have their own metabolism and rely on the metabolism of host cells to provide energy and metabolic substances for their life cycles. Increasing evidence suggests that host cells infected with oncogenic viruses have dramatically altered metabolic requirements and that oncogenic viruses produce substances used for viral replication and virion production by altering host cell metabolism. We focused on the processes by which oncogenic viruses manipulate host lipid metabolism and the lipid metabolism disorders that occur in oncogenic virus-associated diseases. A deeper understanding of viral infections that cause changes in host lipid metabolism could help with the development of new antiviral agents as well as potential new therapeutic targets.

The effect of HTLV1 infection on inflammatory and oxidative parameters in the liver, kidney, and pancreases of BALB/c mice

Viral infections are linked to the progression of inflammatory reactions and oxidative stress that play pivotal roles in systemic diseases. To confirm this phenomenon, in the present study, TNF‐α level and oxidative stress markers were examined in the liver, kidney, and pancreas of HTLV1‐infected male BALB/c mice. To this end, twenty BALB/c mice were divided into HTLV1‐infected mice that were inoculated with 1‐million HTLV1‐infected cells (MT‐2), and the control groups. Two months after inoculation, the peripheral blood, mesenteric lymph nodes, liver, kidney, and pancreas were collected after deep anesthetization of mice (ketamine, 30 mg/kg). The extracted DNA of mesenteric lymph nodes was obtained to quantify proviral load (PVL) using quantitative real‐time polymerase chain reaction (qRT‐PCR). The levels of lipid peroxidation, total thiol (SH), nitric oxide (NO), TNF‐α, catalase (CAT), and superoxide dismutase (SOD) activities were examined in the liver, kidney, and pancreases. Furthermore, histopathological changes in the liver and kidney were evaluated. In liver tissue, the levels of MDA, TNF‐α, and blood cell infiltration were significantly increased, and the levels of CAT and SOD were significantly decreased. In the kidney, a reduction in SOD, CAT, and total SH and an increase in MDA and NO were observed. In the pancreas, CAT activity, total SH, and SOD were decreased, and the levels of MDA and NO were enhanced. In terms of TNF‐α production, it has been shown that the level of this inflammatory cytokine was increased in the liver, kidney, and pancreas. The HTLV1 may have a role in inducing inflammatory reactions and oxidative stress pathways in the tissues.

Human T lymphotropic virus type 1 and risk of cardiovascular disease: High-density lipoprotein dysfunction versus serum HDL-C concentrations

High-density lipoprotein (HDL) is thought to be protective against cardiovascular disease (CVD), and HDL dysfunction is considered to be a risk factor for CVD. It is unclear whether there is an association between Human T lymphotropic virus type 1 (HTLV1) infection and CVD risk. We have assessed HDL lipid peroxidation (HDLox) as a marker of HDL dysfunction and CVD risk in a subgroup of the MASHAD cohort study. One hundred and sixty two individuals including 50 subjects positive for HTLV1 infection and 112 individuals negative for HTLV1 infection were recruited. Anthropometric and biochemical parameters including serum hs-CRP, fasted lipid profile (HDL-C, LDL, triglycerides, and cholesterol), and fasting blood glucose were determined. Serum HDLox was also measured in the study participants. Multivariate analyses were used to evaluate the association between serum HDLox and HTLV1 infection. None of the traditional CVD risk factors were associated with HTLV1 infection, including serum HDL-C. However, serum HDLox was independently associated with the presence of HTLV1 infection. Logistic regression analysis showed that subjects who were positive for HTLV1 infection were also significantly more likely than uninfected individuals to have higher HDLox (odds ratio 9.35, 95%CI: 3.5-24.7; P < 0.001). HDLox was increased approximately 20% (P < 0.001) in infected subjects compared to the uninfected group. Serum HDLox is a marker of CVD risk factor and increased in individuals affected by HTLV1 infection compared to healthy subjects. © 2019 BioFactors, 45(3):374-380, 2019.

Curbing Lipids: Impacts ON Cancer and Viral Infection

Lipids play a fundamental role in maintaining normal function in healthy cells. Their functions include signaling, storing energy, and acting as the central structural component of cell membranes. Alteration of lipid metabolism is a prominent feature of cancer, as cancer cells must modify their metabolism to fulfill the demands of their accelerated proliferation rate. This aberrant lipid metabolism can affect cellular processes such as cell growth, survival, and migration. Besides the gene mutations, environmental factors, and inheritance, several infectious pathogens are also linked with human cancers worldwide. Tumor viruses are top on the list of infectious pathogens to cause human cancers. These viruses insert their own DNA (or RNA) into that of the host cell and affect host cellular processes such as cell growth, survival, and migration. Several of these cancer-causing viruses are reported to be reprogramming host cell lipid metabolism. The reliance of cancer cells and viruses on lipid metabolism suggests enzymes that can be used as therapeutic targets to exploit the addiction of infected diseased cells on lipids and abrogate tumor growth. This review focuses on normal lipid metabolism, lipid metabolic pathways and their reprogramming in human cancers and viral infection linked cancers and the potential anticancer drugs that target specific lipid metabolic enzymes. Here, we discuss statins and fibrates as drugs to intervene in disordered lipid pathways in cancer cells. Further insight into the dysregulated pathways in lipid metabolism can help create more effective anticancer therapies.

Proteomic analysis of plasma extracellular vesicles reveals mitochondrial stress upon HTLV-1 infection

Extracellular vesicles (EVs) can participate in intercellular communication and pathogenesis. EVs contain many cargos, including proteins, and the composition of EVs differs between cell-types and activation levels. Thus, plasma EVs can be used as a biomarker of systemic response to infection and/or disease progression. In this study, we aimed at describing alterations in the protein content of plasma EVs upon infection with the human T-lymphotropic retrovirus type 1 (HTLV-1). HTLV-1 is the etiological agent of a lymphoproliferative disease (ATL) and a series of inflammatory diseases, including a neurodegenerative inflammatory disease (HAM/TSP). We found that plasma EVs are more abundant and smaller in HTLV-1 asymptomatic carriers or HAM/TSP patients when compared to uninfected healthy donors. Moreover, EVs from HTLV-1 infected donors contain markers of metabolic and mitochondrial stress.