Pathophysiology, Volume 32, Issue 3 (September 2025) – 7 articles

Fetal alcohol spectrum disorder (FASD) is a preventable cause of developmental disabilities linked to prenatal alcohol exposure (PAE). Congenital heart defects (CHDs) are frequently observed in FASD, with a notable association between PAE and dextro-type transposition of the great arteries (d-TGA). A potential pathogenetic mechanism of d-TGA in FASD, involving retinoic acid (RA) deficiency due to the interference of ethanol with RA biosynthesis, is proposed. Further investigation is required to understand the timing and impact of alcohol exposure on congenital anomalies, particularly in the context of CHDs. Full article

Despite the growing morbidity associated with alcohol use disorder (AUD), current FDA-approved therapeutics fail to adequately address the condition. This is in part due to the complex systemic effects of ethanol (EtOH), which have particularly negative consequences on the gut–liver–brain axis. Importantly, two systemic mechanisms underlying the progression of AUD remain underemphasized in therapeutic development: thiamine deficiency and neuroinflammation. Alcohol-induced thiamine deficiency leads to reduced activity of key metabolic enzymes, thereby resulting in energy deficits, oxidative stress, and severe clinical implications. EtOH also activates TLR4 and NLRP3, both of which play critical roles in the regulation of neuroimmune responses. While research directly investigating the relationship between thiamine deficiency and neuroinflammation is still in its early stages, our review highlights the emerging connections between these two seemingly distinct pathomechanisms. Additionally, potential therapeutic approaches and targets for addressing AUD at a systemic level are discussed. Full article

Renal function refers to the combined actions of the glomerulus and tubular system to achieve homeostasis in bodily fluids. While the glomerulus is essential in the first step of urine formation through a coordinated filtration mechanism, the tubular system carries out active mechanisms of secretion and reabsorption of solutes and proteins using specific transporters in the epithelial cells. The assessment of renal function usually focuses on glomerular function, so the tubular function is often underestimated as a fundamental part of daily clinical practice. Therefore, it is essential to properly understand the tubular physiological mechanisms and their clinical association with prevalent human pathologies. This review discusses the primary solutes handled by the kidneys, including glucose, amino acids, sodium, potassium, calcium, phosphate, citrate, magnesium and uric acid. Additionally, it emphasizes the significance of physicochemical characteristics of urine, such as pH and osmolarity. The use of a concise methodology for the comprehensive assessment of urine should be strengthened in the basic training of nephrologists when dealing with problems such as water and electrolyte balance disorders, acid-base disorders, and harmful effects of commonly used drugs such as chemotherapy, antibiotics, or diuretics to avoid isolated replacement of the solute without carrying out comprehensive approaches, which can lead to potentially severe complications. Full article

Background: This study investigated the impact of crack cocaine smoke exposure on the submandibular salivary gland of Wistar rats. Methods: The animals were distributed into four groups: control (CTRL); 25 mg exposure (CK25); 50 mg exposure (CK50); and 100 mg exposure (CK100). The animals were exposed to crack cocaine smoke once a day for five consecutive days. Results: Exposure to crack cocaine smoke-induced histopathological changes in submandibular salivary glands in all groups under exposure. The immunohistochemical analysis demonstrates that exposure to crack cocaine smoke led to an increase in BCL-2 and P16 expression in all groups exposed to crack cocaine (p < 0.05). The analysis of Ki-67 expression revealed a significant increase in immunoreactive cells across all exposure groups (p < 0.05). Although MYD88 expression was observed in all crack cocaine-exposed groups, only the group treated with the highest dose (100 mg) exhibited a statistically significant increase compared to the control group (p < 0.05). Conclusions: In summary, this study demonstrates that exposure to crack cocaine smoke-induced tissue degeneration in the submandibular salivary gland, increasing cellular senescence and promoting compensatory cell proliferation in Wistar rats. Full article

Amyloidosis, often referred to as “the great imitator”, is a condition characterized by the abnormal deposition of amyloid proteins in various tissues, potentially leading to organ dysfunction. When these deposits localize in the brain, they can disrupt neurological function and present with diverse clinical manifestations, making diagnosis particularly challenging. Cerebral amyloidosis is a rare entity that frequently mimics other neurological disorders, often resulting in significant delays in recognition and management. This case highlights the diagnostic challenge posed by cerebral amyloidosis and underscores its unique presentation. We present the case of a 76-year-old male with a history of rheumatoid arthritis (RA) who developed progressive right-sided weakness over several months. Three years prior, he experienced numbness on the right side of his face and upper limb. Initial imaging identified a small lesion in the left thalamic region, which was originally diagnosed as a glioma. However, due to the worsening of his clinical symptoms, further evaluation was warranted. Subsequent imaging revealed lesion growth, prompting a biopsy that ultimately confirmed the diagnosis of intracerebral amyloidoma. This case underscores the necessity of considering amyloidosis in the differential diagnosis of atypical neurological deficits, particularly in patients with systemic inflammatory conditions such as RA. The initial presentation of hemiparesis resembling a stroke, coupled with non-specific imaging findings and a prior misdiagnosis of glioma, highlights the complexity of cerebral amyloidosis. Only through brain biopsy was the definitive diagnosis established, emphasizing the need for improved diagnostic modalities to facilitate early detection. Further subtyping of amyloidosis, however, requires mass spectrometry-based proteomics or immunohistochemistry to accurately identify the specific amyloid protein involved. Clinicians should maintain a high index of suspicion for cerebral amyloidosis in patients with RA who present with progressive neurological deficits and atypical brain lesions. Early recognition and accurate diagnosis are essential to guiding appropriate management and improving patient outcomes. Full article

Background: Although immune complex formation is widely acknowledged as the etiological agent for the development of systemic lupus erythematosus, polyarteritis nodosa, reactive arthritis, etc., its roles in chronic hepatitis are less understood. This study aims to compare the immunohistochemistry profile of immune complex deposition in patients with chronic hepatitis B (CHB) and autoimmune hepatitis (AIH). Methods: Immunohistochemistry of C4d, a widely used marker for complement deposition was employed on liver biopsies from 72 and 15 patients with CHB and AIH, respectively. Statistical analysis was performed to analyze its prevalence and its association with a range of clinical and histological parameters. Results: Among the 15 AIH biopsies examined, C4d deposition was observed in 11 cases (73.3%), the majority of which showed a periportal staining pattern (10/11). In CHB, 61 (84.7%) of 72 cases tested positive for C4d, which did not differ significantly with that of AIH. While the periportal pattern was predominantly observed in CHB cases, positive staining in central veins, sinusoids, and hepatic parenchyma were also documented. In particular, C4d deposition is significantly associated with elevated serum ALT and liver inflammation in CHB. Of note, in specimens with a patchy parenchymal C4d staining pattern, a spatially correlated HBsAg IHC signal was observed in adjacent sections from the same tissue. Conclusions: These data suggest an involvement of immune complex-mediated immunopathy in autoimmune hepatitis and HBV-induced hepatitis. The positive intrahepatic C4d signal was associated with heightened liver inflammation. The colocalization of the C4d signal on hepatocytes with HBsAg strongly suggests a causal relationship between viral activity and complement deposition. These observations align with our recent evidence implicating the contribution of capsid–antibody complexes in the pathogenesis of CHB. Full article

Background/Objectives: Diabetic ketoacidosis (DKA) is an acute and severe complication of diabetes mellitus, marked by hyperglycemia, ketosis, and acidosis. It is associated with significant metabolic and inflammatory adjustments that can impact multiple biochemical pathways. This study aimed to determine the serum sphingolipid profile in DKA and investigate its relationship with neutral sphingomyelinase (N-SMase), pro-inflammatory cytokines, β-hydroxybutyrate (β-OHB), and lactate levels. Methods: Thirty-three participants were divided into three groups: control (BMI ≤ 30, no health issues), obese (BMI > 30), and DKA (BMI ≤ 30). Sphingomyelins (16:0–24:0 SMs) and ceramides (C16–C24 CERs) were measured using ultra-fast liquid chromatography combined with tandem mass spectrometry (LC-MS/MS). N-SMase, interleukin 1 beta (IL-1β), and tumor necrosis factor alpha (TNF-α) levels were assessed by enzyme-linked immunosorbent assay. Evaluations were done in the DKA group before and after standard clinical treatment for DKA (post-DKA group), which included intravenous insulin therapy, fluid resuscitation, and electrolyte replacement, as per established clinical guidelines. Results: β-OHB levels were significantly higher in the DKA group than in the control, obese, and post-DKA groups. Although β-OHB levels decreased in the post-DKA group, they remained elevated compared to the control and obese groups. Lactate levels were also higher in the DKA group, with a significant decrease in the post-DKA group. TNF-α and IL-1β were higher in the obese group compared to control and DKA groups, and TNF-α decreased significantly in the post-DKA group compared to DKA. N-SMase, 16:0–18:0 SMs, and C18-C24 CER levels were lower in the DKA and post-DKA groups compared to obese and control groups. Serum β-OHB and lactate levels were significantly correlated with S1P, total CER, total SM, and N-SMase values. Conclusions: The study reveals significant metabolic and inflammatory differences in DKA and post-DKA states, suggesting a relationship between sphingolipids, N-SMase, and these alterations, which could offer insights into DKA pathophysiology and therapeutic targets. Full article