Seong Hoon Goh

Volatile organic compounds (VOCs) are highly volatile chemicals in natural and anthropogenic environments, significantly affecting indoor air quality. Major sources of indoor VOCs include emissions from building materials, furnishings, and consumer products. Natural wood products release VOCs, including terpenes and aldehydes, which exert diverse health effects ranging from mild respiratory irritation to severe outcomes, such as formaldehyde-induced carcinogenicity. The temporal dynamics of VOC emissions were investigated, and the toxicological and physiological effects of the VOCs emitted by two types of natural wood, Korean Red Pine (Pinus densiflora) and Japanese Cypress (Chamaecyparis obtusa), were evaluated. Using female C57BL/6 mice as an animal model, the exposure setups included phytoncides, formaldehyde, and intact wood samples over short- and long-term durations. The exposure effects were assessed using oxidative stress markers, antioxidant enzyme activity, hepatic and renal biomarkers, and inflammatory cytokine profiles. Long-term exposure to Korean Red Pine and Japanese Cypress wood VOCs did not induce significant pathological changes. Japanese Cypress exhibited more distinct benefits, including enhanced oxidative stress mitigation, reduced systemic toxicity, and lower pro-inflammatory cytokine levels compared to the negative control group, attributable to its more favorable VOC emission profile. These findings highlight the potential health and environmental benefits of natural wood VOCs and offer valuable insights for optimizing timber use, improving indoor air quality, and informing public health policies.

Plywood and particle boards, commonly used in construction and interior environments, are sources of indoor chemical emissions from synthetic adhesives, resins, and surface treatments. Among these, formaldehyde, classified as a group 1 carcinogen by the International Agency for Research on Cancer, and other compounds are associated with oxidative stress, inflammation, and organ toxicity. This study aimed to evaluate the toxicological and physiological effects of plywood and particleboard emissions in female C57BL/6 mice. The mice were exposed to formaldehyde, phytoncides, and untreated wood samples under short- (30–60 days) and long-term (120–180 days) conditions. Biological effects were assessed through histopathology of major organs, differential white blood cell counts, oxidative stress markers, antioxidant enzyme activities (catalase and glutathione peroxidase), liver and kidney function tests (alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, and creatinine), and inflammatory cytokine profiling (interferon-gamma, tumor necrosis factor-α, interleukin (IL)-10, and IL-12p70). These findings revealed no significant pathological changes or systemic toxicity following long-term exposure. Minor elevations in hepatic and renal biomarkers were observed but remained within physiological limits. Antioxidant responses and cytokine fluctuations suggested mild adaptive and immunomodulatory effects. These results highlight the importance of reducing emissions from engineered wood products to improve indoor air quality and minimize potential health risks.

Chronic constipation is a common symptom-based disorder that affects patient quality of life. Electrolyzed hydrogen-rich alkaline reduced water (EHARW) helps treat gastrointestinal disorders owing to its various bioactive properties. This single-arm, open-labelled study aimed to investigate the improvement of EHARW (pH 9.5; H₂ ≈ 0.5 mg/L) in chronic constipation patients. Thirty patients with chronic constipation were enrolled after screening as intention-to-treat (ITT). During the intervention period, two patients dropped out, and 28 patients completed the study as per protocol (PP). The selected patients were instructed to drink EHARW (pH 9.5; H₂ ≈ 0.5 mg/L) (20 mL/kg body weight/day) generated from a home medical device for four weeks. Complete spontaneous bowel movement (CSBM) frequency was measured as the primary outcome, and Bristol stool form, patient assessment of constipation–symptoms (PAC-SYM) score, and patient assessment of constipation–quality of life (PAC-QOL) score were measured as the secondary outcomes after the 4-week intervention compared to baseline. As a result of EHARW treatment, no adverse events were observed during the study period. Moreover, the frequency of CSBM/week (29.8%, p < 0.05) and Bristol stool form score (24.6%, p < 0.01) significantly increased compared to baseline. Finally, the overall and subscale scores of the PAC-SYM (58.0%) and PAC-QOL (54.2%) questionnaires significantly decreased (p < 0.001). These results suggest that daily ingestion of EHARW (pH 9.5; H₂ ≈ 0.5 mg/L) can improve CSBM frequency as a primary outcome in chronic constipation patients. Likewise, EHARW (pH 9.5; H₂ ≈ 0.5 mg/L) improved Bristol stool form score, symptoms and the quality of life as a secondary outcome in patients with chronic constipation through a home-based intervention.

Molecular hydrogen (H₂) is a versatile therapeutic agent. H₂ gas inhalation is reportedly safe and has a positive impact on a range of illnesses, including Alzheimer’s disease (AD). Herein, we investigated the effects of 4 weeks of H₂ gas inhalation on community-dwelling adults of various ages. Fifty-four participants, including those who dropped out (5%), were screened and enrolled. The selected participants were treated as a single group without randomization. We evaluated the association between total and differential white blood cell (WBC) counts and AD risk at individual levels after 4 weeks of H₂ gas inhalation treatment. The total and differential WBC counts were not adversely affected after H₂ gas inhalation, indicating that it was safe and well tolerated. Investigation of oxidative stress markers such as reactive oxygen species and nitric oxide showed that their levels decreased post-treatment. Furthermore, evaluation of dementia-related biomarkers, such as beta-site APP cleaving enzyme 1 (BACE-1), amyloid beta (Aβ), brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor A (VEGF-A), T-tau, monocyte chemotactic protein-1 (MCP-1), and inflammatory cytokines (interleukin-6), showed that their cognitive condition significantly improved after treatment, in most cases. Collectively, our results indicate that H₂ gas inhalation may be a good candidate for improving AD with cognitive dysfunction in community-dwelling adults of different ages.

Recently, non-electrolyzed HOCl water has gained the attention of researchers as a new disinfecting agent owing to its high sterilization power, easy accessibility, and safety. Non-electrolyzed HOCl water was developed through mixing at a specific ratio based on hypochlorite and mineral supplements, which revealed a high oxidizing power. In this study, we investigated the effects of non-electrolyzed HOCl water on Helicobacter pylori (H. pylori) infection in C57BL/6 mice over 10 weeks. Mice were divided into three groups: normal control (NC) group supplied with purified water (PW) without infection, PW + H. pylori group supplied with PW after H. pylori infection, and HOCl + H. pylori group supplied with HOCl after H. pylori infection. Our findings demonstrated that the HOCl + H. pylori group greatly inhibited WBC and its differential counts, including total white blood cell (WBC), neutrophils, lymphocytes, monocytes, and eosinophils, when compared to the PW + H. pylori group. Accordingly, the amount of reactive oxygen species and calcium activity significantly decreased in the HOCl + H. pylori group compared to the PW + H. pylori group in both serum and stomach lysates. In contrast, HOCl water treatment enhanced GPx activity compared to PW treatment after H. pylori infection in both serum and stomach lysates. Accordingly, the levels of granulocyte-macrophage colony-stimulating factor, IL-1β, and TNF-α cytokine levels were significantly decreased in the HOCl + H. pylori group compared to those in the PW + H. pylori group in the stomach lysate; however, there was no significant difference in serum. In addition, the expression levels of Bax, MMP-3, MMP-9, and TLR-4 were found to decrease after HOCl water treatment, whereas the expression level of Bcl-2 was found to be enhanced after HOCl water treatment in the stomach lysate. Taken together, our results suggest that drinking non-electrolyzed HOCl water has positive anti-oxidative, anti-inflammatory, and anti-apoptotic effects in H. pylori-infected mice through redox and immune regulation.

Natural products derived from plants, as well as their bioactive compounds, have been extensively studied in recent years for their therapeutic potential in a variety of neurodegenerative diseases (NDs), including Alzheimer’s (AD), Huntington’s (HD), and Parkinson’s (PD) disease. These diseases are characterized by progressive dysfunction and loss of neuronal structure and function. There has been little progress in designing efficient treatments, despite impressive breakthroughs in our understanding of NDs. In the prevention and therapy of NDs, the use of natural products may provide great potential opportunities; however, many clinical issues have emerged regarding their use, primarily based on the lack of scientific support or proof of their effectiveness and patient safety. Since neurodegeneration is associated with a myriad of pathological processes, targeting multi-mechanisms of action and neuroprotection approaches that include preventing cell death and restoring the function of damaged neurons should be employed. In the treatment of NDs, including AD and PD, natural products have emerged as potential neuroprotective agents. This current review will highlight the therapeutic potential of numerous natural products and their bioactive compounds thatexert neuroprotective effects on the pathologies of NDs.

Oxidative stress (OS) and neuroinflammatory stress affect many neurological disorders. Despite the clinical significance of oxidative damage in neurological disorders, still, no effective and safe treatment methods for neuro diseases are available. With this, molecular hydrogen (H₂) has been recently reported as an antioxidant and anti-inflammatory agent to treat several oxidative stress-related diseases. In animal and human clinical trials, the routes for H₂ administration are mainly categorized into three types: H₂ gas inhalation, H₂ water dissolving, and H₂-dissolved saline injection. This review explores some significant progress in research on H₂ use in neurodegenerative diseases (NDs), including Alzheimer’s disease, Parkinson’s disease, neonatal disorders of the brain, and other NDs (retinal ischemia and traumatic brain injury). Even though most neurological problems are not currently curable, these studies have shown the therapeutic potential for prevention, treatment, and mitigation of H₂ administration. Several possible H₂-effectors, including cell signaling molecules and hormones, which prevent OS and inflammation, will also be addressed. However, more clinical and other related studies are required to evaluate the direct H₂ target molecule.