Recent interest in preventing the development of osteoporosis has focused on the regulation of redox homeostasis. However, the action of lycopene (LYC), a strong natural antioxidant com-pound, on osteoporotic bone loss remains largely unknown. Here, we show that the administra-tion of LYC to OVX rats reduces body weight gain, improves lipid metabolism and preserves bone quality. In addition, LYC treatment inhibits ROS overgeneration in serum and bone marrow in OVX rats, and in BMSCs upon H2O2 stimulation, leading to inhibiting adipogenesis and pro-moting osteogenesis during bone remodeling. Mechanically, LYC may improve bone quality via an increase in the expressions of FoxO1 and Runx2, and a decrease in the expressions of PPARγ and C/EBPα in OVX rats and BMSCs. Collectively, these findings suggest that LYC attenuates osteoporotic bone loss through promoting osteogenesis and inhibiting adipogenesis via regula-tion of the FoxO1/PPARγ pathway driven by oxidative stress, presenting a novel strategy for os-teoporosis management.

This review provides information on acne transcriptomics allowing deeper insights into acne pathogenesis and isotretinoin´s mode of action. Puberty-induced insulin-like growth factor 1 (IGF-1), insulin and androgen signaling activate the kinase AKT and mechanistic target of rapamycin complex 1 (mTORC1). Western diet (hyperglycemic carbohydrates, milk/dairy products) as well co-stimulate AKT/mTORC1 signaling. AKT-mediated phosphorylation of nuclear FoxO1 and FoxO3 results in their extrusion into the cytoplasm, a critical switch, which enhances the transactivation of lipogenic and proinflammatory transcription factors including androgen receptor (AR), sterol regulatory element-binding transcription factor 1 (SREBF1), peroxisome proliferator-activated receptor γ (PPARγ), and signal transducer and activator of transcription 3 (STAT3) but reduces FoxO1-dependent expression of GATA binding protein 6 (GATA6), the key transcription factor of infundibular keratinocyte homeostasis. AKT-mediated phosphorylation of the p53-binding protein MDM2 promotes the degradation of p53. In contrast, isotretinoin enhances the expression of p53, FoxO1 and FoxO3 in sebaceous glands of acne patients. Overexpression of these proapoptotic transcription factors explains isotretinoin´s desired sebum-suppressive effect via induction of sebocyte apoptosis but also its adverse effects including teratogenicity (neural crest cell apoptosis), reduced ovarian reserve (granulosa cell apoptosis), risk of depression (apoptosis of hypothalamic neurons), VLDL hyperlipidemia, intracranial hypertension and dry skin.

The risk of lung exposure to silica nanoparticles (SiNPs) and related lung inflammatory injury is increasing with the wide application of SiNPs in a variety of industries. A growing body of research has revealed that cyclooxygenase (COX)-2/ prostaglandin E2 (PGE2) up-regulated by SiNPs toxicity has a role during pulmonary inflammation. The detailed mechanisms underlying SiNPs-induced COX-2 expression and PGE2 synthesis remain unknown. The present study aims to dissect the molecular components involved in COX-2/PGE2 up-regulated by SiNPs in human pulmonary alveolar epithelial cells (HPAEpiCs) which are one of the major targets while SiNPs are inhaled. In the present study, we demonstrated that SiNPs induced COX-2 expression and PGE2 release, which were inhibited by pretreatment with a reactive oxygen species (ROS) scavenger (edaravone) or the inhibitors of proline-rich tyrosine kinase 2 (Pyk2, PF-431396), epidermal growth factor receptor (EGFR, AG1478), phosphatidylinositol 3‑kinase (PI3K, LY294002), protein kinase B (Akt, Akt inhibitor VIII), p38 mitogen-activated protein kinase (MAPK) (p38 MAPK inhibitor VIII), c-Jun N-terminal kinases (JNK)1/2 (SP600125), Forkhead Box O1 (FoxO1, AS1842856), and activator protein 1 (AP-1, Tanshinone IIA). In addition, we also found that SiNPs induced ROS-dependent Pyk2, EGFR, Akt, p38 MAPK, and JNK1/2 activation in these cells. These signaling pathways induced by SiNPs could further cause c-Jun and FoxO1 activation and translocation from the cytosol to the nucleus. AP-1 and FoxO1 activation could increase COX-2 and PGE2 levels induced by SiNPs. Finally, the COX-2/PGE2 axis might promote the inflammatory responses in HPAEpiCs. In conclusion, we suggested that SiNPs induced COX-2 expression accompanied by PGE2 synthesis mediated via ROS/Pyk2/EGFR/PI3K/Akt/p38 MAPK- and JNK1/2-dependent FoxO1 and AP-1 activation in HPAEpiCs.