Biochemical and immunological studies on erythrocytes superoxide dismutase modified by nitric oxide in patients with alopecia areata: Implications in alopecia patchy persistent and alopecia universalis

Oral delivery of a highly stable superoxide dismutase as a skin aging inhibitor

As an effective antioxidant enzyme, superoxide dismutase (SOD) has been widely used as a food supplement, cosmetic additive, and therapeutic agent. However, oral delivery of SOD is challenging due to its relative instability, limited bioavailability, and low absorption efficiency in the gastrointestinal (GI) tract. We addressed these issues using a highly stable superoxide dismutase (hsSOD) generated from a hot spring microbial sample. This SOD exhibited a specific activity of 5000 IU/mg while retaining its enzymatic activity under low pH environments of an artificial GI system and in the presence of surfactants and various proteolytic enzymes. The inhibitory effects of hsSOD against skin-aging was evaluated under both in vitro and in vivo experiments using fibroblast cell and D-galactose induced aging-mouse models, respectively. Effective oral delivery of hsSOD promises wide applicability in pharmaceutical and food industries.

Alopecia Areata: A Review of the Role of Oxidative Stress, Possible Biomarkers, and Potential Novel Therapeutic Approaches

Alopecia areata (AA) is a dermatological condition characterized by non-scarring hair loss. Exact etiopathogenesis of AA is still unknown although it is known that several factors contribute to the collapse of the hair-follicle (HF)-immune-privileged (IP) site. Oxidative stress (OS) plays an important role in skin diseases. The aim of this review was to clarify the role of OS in AA pathogenesis and diagnosis, and to discuss potential treatment options. Oxidative-stress markers are altered in serum and skin samples of patients with AA, confirming a general pro-oxidative status in patients with AA. OS induces MHC class I chain-related A (MICA) expression in HF keratinocytes that activates the receptor NKG2D, expressed in NK cells and CD8+ T cytotoxic cells leading to destabilization of the HF immune-privileged site through the production of IFN-γ that stimulates JAK1 and JAK2 pathways. OS also activates the KEAP1-NRF2 pathway, an antioxidant system that contributes to skin homeostasis. In addition, a decrease of ATG5 and LC3B in the hair matrix and an increase in p62 levels indicates a reduction of intrafollicular autophagy during the evolution of AA. Potential biomarkers of OS in AA could be: malondialdehyde (MDA), advanced glycation end-products (AGEs), and ischemic-modified albumin (IMA). JAK inhibitors are the new frontier in treatment of AA and the use of nutraceuticals that modulate the OS balance, in combination with standard treatments, represent promising therapeutic tools.

Nitric oxide synthase activity: A novel potential biomarker for predicting Alopecia areata

BACKGROUND

Alopecia areata is a dermatological disease characterized by nonscarring type hair loss. The cause of Alopecia areata not known exactly but studies support that it has an autoimmune etiology in which oxidative stress play an important role.

AIM

This study was conducted to evaluate the level of nitrosative stress in Alopecia areata and to investigate the predictive power of nitrosative stress parameters for Alopecia areata.

PATIENTS/METHODS

Thirty patients diagnosed with Alopecia areata, and 30 healthy controls were included in a prospective, cross-sectional study. In both groups, nitric oxide (NO^· ), peroxynitrite (ONOO^- ), and nitric oxide synthase (NOS) activity as nitrosative stress markers were measured spectrophotometrically in serum samples. The predictive power of nitrosative stress parameters in Alopecia areata and control groups was compared with binary logistic regression and Receiver Operating Characteristic analysis.

RESULTS

NO^· , ONOO^- , and NOS activity were significantly higher in patients with Alopecia areata than in the control group (p = 0.001; p < 0.001; p < 0.001, respectively). A positive correlation was found between the parameters. Significantly, binary logistic regression modeling suggested that increases in NOS (p = 0.003, OR = 1.305, 95% CI = 1.095-1.556) activity were associated with Alopecia areata.

CONCLUSION

According to the data obtained from the present study, patients with Alopecia areata were exposed to potent nitrosative stress. In particular, peroxynitrite, which acts as a bridge between reactive oxygen species and reactive nitrogen species, caused the expansion of the oxidative stress cascade. Nitrosative stress might play a role in the etiopathogenesis of Alopecia areata. Nitrosative stress parameters, particularly NOS activity, may be potential markers for Alopecia areata.

Thymoquinone provides structural protection of human hemoglobin against oxidative damage: Biochemical studies

Hydroxyl radicals (OH^.) are one of the most active reactive oxidants recognized for their deleterious effects to cause protein oxidative damage. Thymoquinone, a monoterpene molecule abundantly present in black cumin and known for its pharmacological activities, but its activity against the OH^.-induced protein oxidative damage has never been explored. This study determined the therapeutic potential of thymoquinone against OH^.-induced oxidative human hemoglobin damage. Novel data demonstrated that thymoquinone provides structural protection of hemoglobin against oxidative damage. Treatment of hemoglobin with OH^. induces hypochromicity at 280 and 405 nm, whereas thymoquinone reversed these hypochromic effects. In addition, OH^. cause significant reduction in tryptophan fluorescence, however thymoquinone also reversed these damaging effects. Thymoquinone also reduces OH^.-induced hydrophobicity and also reduces OH^.-induced carbonylation. Moreover, it also inhibits thermal stabilization of OH^.-hemoglobin complex. SDS-PAGE of unmodified hemoglobin showed four bands, which disappeared upon OH^. treatment and these changes were also retained by thymoquinone. In conclusion, this is the first study that shows the therapeutic potential of thymoquinone against OH^.-induced oxidative damage in human hemoglobin.

Recent advances on endogenous gasotransmitters in inflammatory dermatological disorders

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Endogenous gasotransmitters nitric oxide (NO), carbon monoxide (CO), hydrogen sulfide (H₂S), and potential candidates sulfur dioxide (SO₂), methane (CH₄), hydrogen gas (H₂), ammonia (NH₃) and carbon dioxide (CO₂), are generated within the human body.

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Endogenous and potential gasotransmitters regulate inflammation, vasodilation, and oxidation in inflammatory dermatological disorders.

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Endogenous and potential gasotransmitters play potential roles in psoriasis, atopic dermatitis, acne, and chronic skin ulcers.

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Further research should explore the function of these gases and gas donors and inhibitors in inflammatory dermatological disorders.

Background

Endogenous gasotransmitters are small gaseous mediators that can be generated endogenously by mammalian organisms. The dysregulation of the gasotransmitter system is associated with numerous disorders ranging from inflammatory diseases to cancers. However, the relevance of these endogenous gasotransmitters, prodrug donors and inhibitors in inflammatory dermatological disorders has not yet been thoroughly reviewed and discussed.

Aim of review

This review discusses the recent progress and will provide perspectives on endogenous gasotransmitters in the context of inflammatory dermatological disorders.

Key scientific concepts of review

Endogenous gasotransmitters nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H₂S) are signaling molecules that regulate several physiological and pathological processes. In addition, sulfur dioxide (SO₂), methane (CH₄), hydrogen gas (H₂), ammonia (NH₃), and carbon dioxide (CO₂) can also be generated endogenously and may take part in physiological and pathological processes. These signaling molecules regulate inflammation, vasodilation, and oxidative stress, offering therapeutic potential and attracting interest in the field of inflammatory dermatological disorders including psoriasis, atopic dermatitis, acne, rosacea, and chronic skin ulcers. The development of effective gas donors and inhibitors is a promising alternative to treat inflammatory dermatological disorders with controllable and precise delivery in the future.

Does oxidative stress correlate with disease activity and severity in alopecia areata? An analytical study

BACKGROUND

Oxidative stress (OS) has been implicated as a contributory factor in the multifactorial etiopathogenesis of alopecia areata (AA). But with the existing data, it is unclear whether OS is a cause or effect of the disease state in Alopecia areata.

AIMS

To compare the OS parameters viz.malon-di-aldehyde (MDA), superoxide dismutase (SOD), total antioxidant status (TAS) in serum of patients with alopecia areata versus age and sex matched controls, and assess their correlation with the severity of the disease.

PATIENTS/METHODS

Forty clinically diagnosed patients of alopecia areata and forty (n = 40) age and sex-matched healthy controls were recruited. ELISA was used for the evaluation of MDA, and spectrophotometric method was used to evaluate serum TAS and whole blood SOD.

RESULTS

Mean serum TAS and whole blood SOD levels of cases were significantly lower than controls (p = 0.005 and p = 0.002, respectively). Mean serum MDA level of patients was significantly higher compared to controls (p = 0.001). While levels of serum TAS and whole blood SOD were found to decrease from mild to severe grades of disease (p = 0.003, p < 0.001 respectively), levels of MDA increased with increasing disease severity (p < 0.001).

CONCLUSION

The OS parameters were deranged in all subsets of AA, with the greatest derangement seen with whole blood SOD levels.

Elevated Levels of Protein Carbonylation in Patients With Diabetic Nephropathy: Therapeutic and Diagnostic Prospects

BACKGROUND

Oxidative stress-induced protein oxidation has been reported in diabetes mellitus; however a relationship between protein carbonylation and diabetic nephropathy remains to be determined. This study was undertaken to investigate a correlation between protein carbonylation and diabetic nephropathy.

METHODS

Sera from 153 patients with diabetic nephropathy and 142 healthy humans were selected and protein carbonylation was compared. The glycated hemoglobin (Hb_A1C), postprandial blood glucose (PPBG), disease duration (DD) and serum creatinine were analyzed and were correlated with the levels of protein oxidation.

RESULTS

Protein carbonylation was more pronounced in patients with diabetic nephropathy as compared with healthy humans (P < 0.001). The data showed a positive correlation between protein oxidation and Hb_A1C (P < 0.001, r = 0.752); the carbonylation was high in those patients with high Hb_A1C (P < 0.01). The data also showed an important correlation between protein oxidation and PPBG (P < 0.0001, r = 0.680); the carbonyl contents were higher in those patients with higher PPBG (P < 0.001). Results also pointed out a positive correlation of protein oxidation with patients DD (P < 0.001, r = 0.769). Importantly, elevated levels of carbonylation in patients with diabetic nephropathy were also correlated with the elevated levels of serum creatinine.

CONCLUSIONS

This is the first study that shows a positive correlation between protein carbonylation and diabetic nephropathy. The higher carbonylation in patients with higher Hb_A1C, blood glucose, DD or serum creatinine indicate that oxidative modifications in proteins play a key role in the progression of diabetic nephropathy.

iNOS inhibits hair regeneration in obese diabetic (ob/ob) mice

Previous studies have shown that androgenic alopecia is associated with metabolic syndrome and diabetes. However, the detailed mechanism whereby diabetes causes alopecia still remains unclear. We focused on the inflammatory response that is caused by diabetes or obesity, given that inflammation is a risk factor for hair loss. Inducible nitric oxide synthase (iNOS) is known to be upregulated under conditions of acute or chronic inflammation. To clarify the potential role of iNOS in diabetes-related alopecia, we generated obese diabetic iNOS-deficient (ob/ob; iNOS-KO mice). We observed that ob/ob; iNOS-KO mice were potentiated for the transition from telogen (rest phase) to anagen (growth phase) in the hair cycle compared with iNOS-proficient ob/ob mice. To determine the effect of nitric oxide (NO) on the hair cycle, we administered an iNOS inhibitor intraperitoneally (compound 1400 W, 10 mg/kg) or topically (10% aminoguanidine) in ob/ob mice. We observed that iNOS inhibitors promoted anagen transition in ob/ob mice. Next, we administered an NO donor (S-nitrosoglutathione, GSNO), to test whether NO has the telogen elongation effects. The NO donor was sufficient to induce telogen elongation in wild-type mice. Together, our data indicate that iNOS-derived NO plays a role in telogen elongation under the inflammatory conditions associated with diabetes in mice.

Recognition of oxidized albumin and thyroid antigens by psoriasis autoantibodies. A possible role of reactive-oxygen-species induced epitopes in chronic plaque psoriasis

OBJECTIVES

To investigate the role of reactive-oxygen-species (ROS) induced epitopes on human-serum-albumin (HSA) and thyroid antigens in psoriasis autoimmunity.  

METHODS

This study was performed in the College of Medicine, Qassim University, Buraidah, Saudi Arabia between May 2014 and February 2015. The study was designed to explore the role of ROS-induced epitopes in psoriasis autoimmunity. Singlet-oxygen (or ROS)-induced epitopes on protein (ROS-epitopes-albumin) was characterized by in-vitro and in-vivo. Thyroid antigens were prepared from rabbit thyroid, and thyroglobulin was isolated from thyroid extract. Immunocross-reactions of protein-A purified anti-ROS-epitopes-HSA-immunoglobulin G (IgGs) with thyroid antigen, thyroglobulin, and their oxidized forms were determined. Binding characteristics of autoantibodies in chronic plaque psoriasis patients (n=26) against ROS-epitopes-HSA and also with native and oxidized thyroid antigens were screened, and the results were compared with age-matched controls (n=22). 

RESULTS

The anti-ROS-epitopes-HSA-IgGs showed cross-reactions with thyroid antigen, thyroglobulin and with their oxidized forms. High degree of specific binding by psoriasis IgGs to ROS-epitopes-HSA, ROS-thyroid antigen and ROS-thyroglobulin was observed. Immunoglobulin G from normal-human-controls showed negligible binding with all tested antigens. Moreover, sera from psoriasis patients had higher levels of carbonyl contents compared with control sera.  

CONCLUSION

Structural alterations in albumin, thyroid antigens by ROS, generate unique neo-epitopes that might be one of the factors for the induction of autoantibodies in psoriasis.

The edaravone and 3-n-butylphthalide ring-opening derivative 10b effectively attenuates cerebral ischemia injury in rats

AIM

Compound 10b is a hybrid molecule of edaravone and a ring-opening derivative of 3-n-butylphthalide (NBP). The aim of this study was to examine the effects of compound 10b on brain damage in rats after focal cerebral ischemia.

METHODS

SD rats were subjected to 2-h-middle cerebral artery occlusion (MCAO). At the onset of reperfusion, the rats were orally treated with NBP (60 mg/kg), edaravone (3 mg/kg), NBP (60 mg/kg)+edaravone (3 mg/kg), or compound 10b (70, 140 mg/kg). The infarct volume, motor behavior deficits, brain water content, histopathological alterations, and activity of GSH, SOD, and MDA were analyzed 24 h after reperfusion. The levels of relevant proteins in the ipsilateral striatum were examined using immunoblotting.

RESULTS

Administration of compound 10b (70 or 140 mg/kg) significantly reduced the infarct volume and neurological deficits in MCAO rats. The neuroprotective effects of compound 10b were more pronounced compared to NBP, edaravone or NBP+edaravone. Furthermore, compound 10b significantly upregulated the protein levels of the cytoprotective molecules Bcl-2, HO-1, Nrf2, Trx, P-NF-κB p65, and IκB-α, while decreasing the expression of Bax, caspase 3, caspase 9, Txnip, NF-κB p65, and P-IκB-α.

CONCLUSION

Oral administration of compound 10b effectively attenuates rat cerebral ischemia injury.