Integrative Proteomics-Metabolomics of In Vitro Degeneration of Cardiovascular Cell Lines.

Long-term cell culture is an important biological approach but is also characterized by degeneration in cellular morphology, proliferation rate, and function. To explore this phenomenon in a systematic way, we conducted an integrative proteomics-metabolomics measurement of two cardiovascular cell lines of AC16 and HUVECs. The 18th culturing passages, i.e., G18, showed as the turning points by cell metabolism profiles, in which the metabolomic changes demonstrated the dysfunction of energy, amino acid, and ribonucleotide metabolism metabolic pathways. Although active protein networks showed mitochondria abundance AC16 and oxidative/nitrative sensitive HUVECs indicated the different degeneration patterns, the G18 and G30 proteomics evidenced the senescence by processes of signal transduction, signaling by interleukins, programmed cell death, cellular responses to stimuli, cell cycle, mRNA splicing, and translation. Some crucial proteins (RPS8, HNRNPR, SOD2, LMNB1, PSMA1, DECR1, GOT2, OGDH, PNP, CBS, ATIC, and IMPDH2) and metabolites (L-glutamic acid, guanine, citric acid, guanosine, guanosine diphosphate, glucose 6-phosphate, and adenosine) that contributed to the dysregulation of cellular homeostasis are identified by using the integrative proteomic-metabolomic analysis, which highlighted the increased cellular instability. These findings illuminate some vital molecular processes when culturing serial passages, which contribute holistic viewpoints of in vitro biology with emphasis on the replicative senescence of cardiovascular cells.

Joint effect of indoor size-fractioned particulate matters and black carbon on cardiopulmonary function and relevant metabolic mechanism: A panel study among school children.

Indoor particulate matter (PM) and black carbon (BC) are associated with adverse cardiopulmonary effect. However, the cumulative and interactive effects of the mixture of size-fractioned PMs and BC on cardiopulmonary function are not well understood, and the underlying biological mechanisms remain unclear. This repeated-measure study was conducted to assess the joint cardiopulmonary effect and metabolic mechanisms of multiple-size particles and BC among 46 children. PM0.5, PM1, PM2.5, PM5, PM10 and BC were monitored for 5 weekdays. Cardiorespiratory function measurements and urine samples collection were conducted three times. Untargeted-metabolomics and meet-in-metabolite approach were applied to mechanism investigation. Bayesian machine kernel regression was adopted to analyze associations among PMs, cardiopulmonary function and metabolites. Lung function and heart rate variability significantly decreased with the increased PMs and BC co-exposure (p < 0.05). The effective particles were BC, PM1-2.5 and PM0.5 in turn. No interaction effects of different particles on cardiopulmonary function were observed at different lag days. BC-related glucose and fatty acid increase, and PM1-2.5-related branched-chain amino acid degradation were primarily observed. Other metabolisms were successively disturbed. The greatest joint effects of PMs and BC on metabolism were mainly at lag0 and lag01 day. They occurred earlier than the strongest effects on cardiopulmonary function, which were at lag01 and lag02 day. BC, PM1-2.5 and PM0.5 were mainly associated with cardiorespiratory indices by disturbing amino acids, glucose, lipid, isoflavone and purine metabolism. Mitochondrial productivity and antioxidation reduction are pivotal to the relevant metabolic alterations. More attention should be paid to BC and smaller-size PMs to control indoor PM pollution and its adverse effect on children.

Real-world particulate matters induce lung toxicity in rats fed with a high-fat diet: Evidence of histone modifications.

Exposure to ambient particulate matters (PMs) has been associated with a variety of lung diseases, and high-fat diet (HFD) was reported to exacerbate PM-induced lung dysfunction. However, the underlying mechanisms for the combined effects of HFD and PM on lung functions remain poorly unraveled. By performing a comparative proteomic analysis, the current study investigated the global changes of histone post-translational modifications (PTMs) in rat lung exposed to long-term, real-world PMs. In result, after PM exposure the abundance of four individual histone PTMs (1 down-regulated and 3 up-regulated) and six combinatorial PTMs (1 down-regulated and 5 up-regulated) were significantly altered in HFD-fed rats while only one individual PTM was changed in rats with normal diet (ND) feeding. Histones H3K18ac, H4K8ac and H4K12ac were reported to be associated with DNA damage response, and we found that these PTMs were enhanced by PM in HFD-fed rats. Together with the elevated DNA damage levels in rat lungs following PM and HFD co-exposure, we demonstrate that PM exposure combined with HFD could induce lung injury through altering more histone modifications accompanied by DNA damage. Overall, these findings will augment our knowledge of the epigenetic mechanisms for pulmonary toxicity caused by ambient PM and HFD exposure.

Environmental doses of arsenic exposure are associated with increased reproductive-age male urinary hormone excretion and in vitro Leydig cell steroidogenesis.

Humans are ubiquitously exposed to arsenic from multiple sources, and chronic arsenic exposure may be associated with male reproductive health. Although association regarding arsenic exposure and sex hormone secretion in blood has been reported, sex hormone excretion in urine studies is lacking. Urinary sex hormone excretion has emerged as a complementary strategy to evaluate gonadal function. Herein, we determined the associations between environmental exposure to arsenic and urinary sex hormone elimination and in vitro Leydig cell steroidogenesis. Concentrations of arsenic and testosterone (T), estradiol (E2) and progesterone (P) in repeated urine samples were determined among 451 reproductive-age males. Moreover, an in vitro Leydig cell MLTC-1 steroidogenesis experiment was designed to simulate real-world scenarios of low human exposure. Multivariable linear regression models were used to assess the associations of urinary arsenic levels with urinary hormones. Urinary arsenic concentrations were positively associated with urinary sex hormone (T, E2, and P) levels. An in vitro test further demonstrated that a population-based environmental exposure range (0.01-5 µM) of arsenic induced Leydig cell steroidogenesis potency. Our results indicate that low-dose arsenic exposure exhibits an endocrine disrupting effect by stimulating Leydig cell steroidogenesis and accelerating urinary steroid excretion, which extends previous knowledge of the inverse association of high-dose arsenic exposure with sexual steroid production that is assumed to be anti-androgen.