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The commentary elucidates the importance of Protection Motivation Theory (PMT) as a theoretical framework to encourage the practice of social distancing in rural areas as the world grappled with the pandemic of COVID-19 outbreak.

Ferroptosis is an iron-dependent form of regulated nonapoptotic cell death, which contributes to damage in models of acute kidney injury (AKI). Heme oxygenase-1 (HO-1) is a cytoprotective enzyme induced in response to cellular stress, and is protective against AKI because of its antiapoptotic and anti-inflammatory properties. However, the role of HO-1 in regulating ferroptosis is unclear. The purpose of this study was to elucidate the role of HO-1 in regulating ferroptotic cell death in renal proximal tubule cells (PTCs). Immortalized PTCs obtained from HO-1+/+ and HO-1−/− mice were treated with erastin or RSL3, ferroptosis inducers, in the presence or absence of antioxidants, an iron source, or an iron chelator. Cells were assessed for changes in morphology and metabolic activity as an indicator of cell viability. Treatment of HO-1+/+ PTCs with erastin resulted in a time- and dose-dependent increase in HO-1 gene expression and protein levels compared with vehicle-treated controls. HO-1−/− cells showed increased dose-dependent erastin- or RSL3-induced cell death in comparison to HO-1+/+ PTCs. Iron supplementation with ferric ammonium citrate in erastin-treated cells decreased cell viability further in HO-1−/− PTCs compared with HO-1+/+ cells. Cotreatment with ferrostatin-1 (ferroptosis inhibitor), deferoxamine (iron chelator), or N-acetyl-l-cysteine (glutathione replenisher) significantly increased cell viability and attenuated erastin-induced ferroptosis in both HO-1+/+ and HO-1−/− PTCs. These results demonstrate an important antiferroptotic role of HO-1 in renal epithelial cells.

Monocytes/macrophages are thought to be recruited to the renal interstitium during calcium oxalate (CaOx) kidney stone disease for crystal clearance. Mitochondria play an important role in monocyte function during the immune response. We recently determined that monocytes in patients with CaOx kidney stones have decreased mitochondrial function compared to healthy subjects. The objective of this study was to determine whether oxalate, a major constituent found in CaOx kidney stones, alters cell viability, mitochondrial function, and redox homeostasis in THP-1 cells, a human derived monocyte cell line. THP-1 cells were treated with varying concentrations of CaOx crystals (insoluble form) or sodium oxalate (NaOx; soluble form) for 24 h. In addition, the effect of calcium phosphate (CaP) and cystine crystals was tested. CaOx crystals decreased cell viability and induced mitochondrial dysfunction and redox imbalance in THP-1 cells compared to control cells. However, NaOx only caused mitochondrial damage and redox imbalance in THP-1 cells. In contrast, both CaP and cystine crystals did not affect THP-1 cells. Separate experiments showed that elevated oxalate also induced mitochondrial dysfunction in primary monocytes from healthy subjects. These findings suggest that oxalate may play an important role in monocyte mitochondrial dysfunction in CaOx kidney stone disease., Graphical abstract fx1, Highlights • Oxalate is a major constituent of calcium oxalate (CaOx) kidney stones and can be found in either soluble or insoluble forms. • CaOx crystals are required for CaOx kidney stone formation. • Monocytes/macrophages play an important role in crystal clearance. • Oxalate causes mitochondrial dysfunction and disrupts redox homeostasis in monocytes.

Acute kidney injury (AKI) is a devastating clinical condition affecting at least two-thirds of critically ill patients, and, among these patients, it is associated with a greater than 60% risk of mortality. Kidney mononuclear phagocytes (MPs) are implicated in pathogenesis and healing in mouse models of AKI and, thus, have been the subject of investigation as potential targets for clinical intervention. We have determined that, after injury, F4/80(hi)-expressing kidney-resident macrophages (KRMs) are a distinct cellular subpopulation that does not differentiate from nonresident infiltrating MPs. However, if KRMs are depleted using polyinosinic/polycytidylic acid (poly I:C), they can be reconstituted from bone marrow–derived precursors. Further, KRMs lack major histocompatibility complex class II (MHCII) expression before P7 but upregulate it over the next 14 days. This MHCII(–) KRM phenotype reappears after injury. RNA sequencing shows that injury causes transcriptional reprogramming of KRMs such that they more closely resemble that found at P7. KRMs after injury are also enriched in Wingless-type MMTV integration site family (Wnt) signaling, indicating that a pathway vital for mouse and human kidney development is active. These data indicate that mechanisms involved in kidney development may be functioning after injury in KRMs.

The development of numerous types of cardiovascular disease is associated with alteration of the vascular smooth muscle cell (SMC) phenotype. We have previously shown that abdominal aortic aneurysm progression in a mouse model of the disease is associated with reduced differentiation of SMCs within the lesion and that cyclooxygenase-2 (COX-2) is critical to initiation and progression of the aneurysms. The current studies utilized human aortic SMC (hASMC) cultures to better characterize mechanisms responsible for COX-2-dependent modulation of the SMC phenotype. Depending on the culture conditions, hASMCs expressed multiple characteristics of a differentiated and contractile phenotype, or a de-differentiated and secretory phenotype. The pharmacological inhibition of COX-2 promoted the differentiated phenotype whereas treatment with the COX-2-derived metabolite prostaglandin E2 (PGE2) increased characteristics of the de-differentiated phenotype. Furthermore, pharmacological inhibition or siRNA-mediated knockdown of microsomal prostaglandin E synthase-1 (mPGES-1), the enzyme that functions down-stream of COX-2 during the synthesis of PGE2, significantly increased expression of characteristics of the differentiated SMC phenotype. Therefore, our findings suggest that COX-2 and mPGES-1 -dependent synthesis of PGE2 contributes to a de-differentiated hASMC phenotype and that mPGES-1 may provide a novel pharmacological target for treatment of cardiovascular diseases where altered SMC differentiation has a causative role.

Cancer incidence and mortality is a significant area of health disparity between African Americans and Caucasians. In the current article the authors used a systematic review design to examine the characteristics of different cancer media education intervention (CMEI) to increase access to cancer screenings for African Americans within a 30 year period (1980-2010). Ten computerized databases were searched using inclusion-exclusion criteria. Consequently, 179 potential studies were identified, and later reduced to 41 eligible studies through the inclusion-exclusion criteria. The eligible studies had a combined sample size of N = 12,764 respondents. The findings revealed that multi-media intervention strategies were the most common media intervention that led to increased cancer screenings among African Americans. The authors conclude with a call for social workers to be more involved in developing and following up with culturally appropriate media strategies that can increase the likelihood of early detection and successful treatment, thus reducing this important area of health disparity.

The immune cellular compartment of the kidney is involved in organ development and homeostasis, as well as in many pathological conditions. Little is known about the mechanisms that drive intrarenal immune responses in the presence of renal tubular and interstitial cell death. However, it is known that tissue-resident leukocytes have the potential to have distinct roles compared with circulating cells. We used a parabiosis model in C57BL/6 CD45 congenic and green fluorescent protein transgenic mice to better understand the dynamics of immune cells in the kidney. We found F4/80Hi intrarenal macrophages exhibit minimal exchange with the peripheral circulation in two models of parabiosis, whether mice were attached for 4 or 16 weeks. Other intrarenal inflammatory cells demonstrate near total exchange with the circulating immune cell pool in healthy kidneys, indicating that innate and adaptive immune cells extensively traffic through the kidney interstitium during normal physiology. Neutrophils, dendritic cells, F4/80Low macrophages, T cells, B cells, and NK cells are renewed from the circulating immune cell pool. However, a fraction of double-negative T (CD4- CD8-) and NKT cells are long-lived or tissue resident. This study provides direct evidence of leukocyte sub-populations that are resident in the renal tissue, cells which demonstrate minimal to no exchange with the peripheral blood. In addition, the data demonstrate continual exchange of other sub-populations through uninflamed tissue.

Most respiratory infections, diseases and allergic reactions have varying degrees of inflammation. Inflammation is a natural immunodefensive response to the presence of allergens or foreign particles that come into contact or affect the cells and tissues within the respiratory tract. The three main types of therapeutic drug classes available for anti-inflammatory and anti-allergy effects are corticosteroids, antihistamines and decongestants. Corticosteroid drugs for pulmonary inhalation and/or nasal delivery include beclomethasone dipropionate, budesonide, ciclesonide, fluticasone furoate, fluticasone propionate, mometasone furoate, and triamcinolone acetonide. Antihistamine drugs for nasal delivery include azelastine and olopatadine. Two common decongestants available are oxymetazoline and phenylephrine. Another therapeutic class, the anticholinergic agents, such as ipratropium bromide and tiotropium bromide, are used in pulmonary delivery in the treatment of inflammatory diseases such as asthma and chronic obstructive pulmonary disease. The mast cell stabilizer therapeutic class, cromolyn sodium, can be used to prevent and relieve nasal allergic symptoms. Additionally cromolyn sodium was the first dry powder inhaler product for pulmonary drug delivery several decades ago and currently is on the market as a pressurized metered dose inhaler for pulmonary inhalation delivery. Based on the devices used in pulmonary drug delivery, this route can be subdivided into three categories; namely nebulizers, pressurized metered dose inhalers, and dry powder inhalers. Nasal delivery of anti-inflammatory and antiallergy drugs is most commonly available commercially in an aqueous spray form. This article comprehensively reviews and discusses different kinds of drugs used for anti-inflammatory and anti-allergic effects via the pulmonary and nasal delivery route, as well as their mechanisms of action, marketed products, disease state indications while highlighting drug delivery and therapeutic aspects.

INTRODUCTION In a mouse model of abdominal aortic aneurysms (AAAs) induced by chronic angiotensin II (AngII) infusion, the effectiveness of cyclooxygenase-2 (COX-2) inhibition in attenuating AAA pr...