A case study on neuro-transmitter shift in prolonged diabetic patients and cure by vitamin supplements

Introduction

Neurotransmitter status in patients with longterm diabetes. Chemical messengers called neurotran smitters control neuronal transmission and are crucial for preserving physiological, emotional, and cognitive processes. Neurotransmitter levels and function are significantly altered in long-term diabetes. (Gispen and Biessels (2000) [16] ; Biessels and Reagan (2015)) [2] . The following are the main neurotransmitter alterations noted:

• Reduced serotonin levels, which are linked to mood disorders and depression (Reagan 2007) [24] .

• Lower dopamine levels, which impact reward systems, motivation, and cognition (Biessels and Reagan, 2015) [2] . A decrease in inhibitory control due to a decrease in gammaaminobutyric acid (GABA) (Kleinridders et al., 2014) [21] .

• Excitotoxic neuronal injury due to elevated glutamate levels (Uttara et al., 2009) [25] .

The main causes of these changes are oxidative damage and metabolic disorders in neuronal cells Patients with diabetes may experience neurobehavioral issues as a result of the neurotransmitter imbalance, which impairs synaptic transmission. (Vincent et al., 2004) [26] . function and increased neurotransmitter breakdown. Emotional disorders and cognitive impairment are mostly caused by dysregulation of neurotransmitter concentration. (Biessels and Gispen, 2000) [16] .

Oxidative Stress and Its Link with Prolonged Diabetes

A central mechanism underlying diabetic complications is Oxidative Stress. Oxidative stress occurs when the production of reactive oxygen species (ROS) exceeds the capacity of antioxidant defense systems. (Brownlee, 2001; Baynes, 1991) [14,11] . In prolonged diabetes:

• Chronic hyperglycemia enhances mitochondrial ROS production (Brownlee, 2001) [14] .

• Activation of metabolic pathways such as the polyol pathway increases oxidative burden

• (Vincent et al., 2004) [26] .

• Advanced glycation end products (AGEs) contribute to cellular damage (Baynes, 1991) [11] .

Oxidative stress leads to lipid peroxidation, protein oxidation, and DNA damage, all of which impair cellular function and viability. (Maritim et al., 2003) [22] .

Oxidative Stress and Changes in Neurotransmitters

Because of its high lipid content and oxygen consumption, the nervous system is especially susceptible to oxidative injury (Halliwell, 2006) [18] . Neurotransmitter systems are directly impacted by oxidative stress in a number of ways:

• Damage to neurotransmitter synthesis-related enzymes (Uttara et al., 2009) [25] .

• Membrane integrity changes that impact the release of neurotransmitters (Halliwell, 2006) [18] .

• Degradative enzyme activity has increased (Vincent, et al., 2004) [26] .

For instance, tryptophan hydroxylase and tyrosine hydroxylase, which are necessary for the synthesis of serotonin and dopamine, respectively, are inhibited by oxidative stress. Lipid peroxidation also affects neuronal membranes, impairing the release of neurotransmitters and the function of synaptic vesicles. (Uttara et al., 2009) [25] .

Neurotransmitter Decrease in Diabetes: A Biochemical Foundation

Patients with diabetes have lower levels of neurotransmitters due to both increased breakdown and decreased synthesis. (Reagan (2007) [24] . Important biochemical elements consist of:

• Oxidative damage-induced deactivation of enzymes (Vincent et al., 2004) [26] .

• Precursors like tryptophan and tyrosine are less readily available (Fernstrom, 2013) [15] .

• Monoamine oxidase (MAO) activity is elevated, resulting in rapid breakdown (Reagan, 2007) [24] . Neurological dysfunction is exacerbated by these metabolic changes, which lead to a net drop in neurotransmitter levels. (Reagan and Biessels, 2015) [2] .

Vitamin Use in Metabolic Disorders

As cofactors, antioxidants, and biochemical pathway regulators, vitamins are vital to metabolic processes. Due to increasing oxidative stress and metabolic demands, vitamin supplementation becomes especially crucial in diabetics (Kennedy, 2016; Harrison and May, 2009) [20,6] . Important vitamins involved: • • Vitamin D3: Has neuroprotective properties and improves insulin sensitivity (Grant, 2011) [5] . • The synthesis of neurotransmitters and nerve function depend on vitamin B complex (Kennedy, 2016) [20] . Vitamin C: Promotes neurotransmitter metabolism and offers antioxidant defence (Harrison and May ( 2009)) [6] . Together, these vitamins enhance metabolic balance and lessen diabetes-related problems (Maritim et al., 2003) [22] .

The Interconnectedness of Neurotransmitters, Oxidative Stress and Diabetes

Diabetes, oxidative stress, and neurotransmitter imbalance are closely related to one another (Brownlee, 2001; Vincent et al., 2004) [26] .

Hyperglycemia is caused by diabetes • Oxidative stress is brought on by hyperglycemia

• Neuronal cells are harmed by oxidative stress • An imbalance in neurotransmitters is caused by injury to neurones.

This cycle underscores the necessity for therapies that target numerous pathways and prolongs the progression of the disease. (Maritim et al., 2003) [22] .

Materials and Methods

The present study was designed as a combined In vitro and In vivo experimental investigation to evaluate the effect of Vitamin D3 supplementation on lipid profile alterations and neurotransmitter shifts associated with diabetes. The study comprised two components:

In vitro analysis using human serum samples to assess biochemical changes in lipid parameters and oxidative stress.

In vivo observation involving a prolonged diabetic patient receiving Vitamin D3 supplementation to monitor changes in neurotransmitter-related symptoms over time.

Materials:

The required materials used were issued and all investigation as well as analytical protocols was conducted in laboratory of CAEHS, Meerut.

Blood Samples: Fasting human blood serum samples were collected from study participants and stored at -80 °C until further analysis.

Chemicals: Vitamin D3 (cholecalciferol, analytical grade) was used for supplementation studies. Organic solvents such as methanol, chloroform, and hexane (HPLC grade) were used throughout the experiment.

Equipments: Standard laboratory equipment, including a UV-visible spectrophotometer, vortex mixer, refrigerated centrifuge, and amber glassware, was employed to ensure precision and prevent photo-degradation.

Methodology

Sample Selection: Three individuals were included in the study:

In-vitro Study: To evaluate the oxidative stress in patients chosen for the study their sample were subjected to following proceduresi) Lipid Isolation: Total lipids were extracted from serum samples using the chloroform-methanol extraction method.

Frozen serum samples were thawed on ice prior to analysis. Briefly, 1 mL of serum was mixed with 10 mL chloroform: methanol (1:2, v/v) and vortexed for 1-2 minutes. Phase separation was achieved by adding 2 mL distilled water, followed by centrifugation at 2000-5000 rpm for 10-15 minutes at 4 °C. The lower chloroform phase containing lipids was collected and transferred to pre-weighed amber vials. The solvent was evaporated under nitrogen gas to obtain dried lipid extracts, which were weighed to determine total lipid content.

ii) Vitamin D3 Supplementation (In vitro): A stock solution of Vitamin D3 (10 µg/mL) was prepared in ethanol and diluted to obtain required working concentrations.

Extracted lipid samples were aliquoted, and Vitamin D3 was added to each sample. The mixtures were vortexed and, where necessary, re-evaporated under nitrogen to obtain lipid-Vitamin D3 complexes.

iii) Incubation and Biochemical Analysis: Samples were flushed with nitrogen, sealed, and incubated at 37 °C for 1-24 hours. After incubation, biochemical parameters were analyzed. Lipid profile parameters, including total cholesterol (TC), triglycerides (TG), HDL, and LDL, were measured using enzymatic colorimetric assay kits. Vitamin D3 levels were quantified using chemiluminescent immunoassay (CLIA).

iv) TBARS Assay: Lipid peroxidation was assessed using the thiobarbituric acid reactive substances (TBARS) assay. Briefly, 100 µL of sample was mixed with SDS, thiobarbituric acid, sodium acetate buffer, and distilled water. The mixture was incubated to allow color development, and absorbance was measured at 532 nm using a spectrophotometer. The intensity of the color corresponded to the level of lipid peroxidation.

In vivo

Results

The study also assessed the impact of diabetes on neurotransmitter levels. A significant reduction in key neurotransmitters such as serotonin and dopamine was observed in the diabetic group compared to the control group, indicating a disturbance in neurotransmission under diabetic conditions. In contrast, subjects receiving vitamin supplementation exhibited improved neurotransmitter levels, suggesting a restorative effect of vitamins on neuronal function.

Comparison of lipid profile among different groups

The diabetic group showed a marked increase in total cholesterol (176 mg/dL) compared to the control group (80 mg/dL). Upon vitamin supplementation, TC levels decreased significantly to 99 mg/dL. Similarly, LDL levels were elevated in the diabetic group (110.4 mg/dL) in comparison to the control (75 mg/dL), whereas vitamin treatment resulted in a substantial reduction to 40.88 mg/dL. HDL levels were found to decrease in the diabetic group (40 mg/dL) as compared to the control (65 mg/dL). However, vitamin supplementation did not significantly improve HDL levels (39.70 mg/dL).Triglyceride levels showed a slight decrease in the diabetic group (128 mg/dL) compared to control (156 mg/dL), and a further reduction was observed following vitamin treatment (92 mg/dL).

The results indicate that diabetes significantly alters lipid metabolism, leading to increased TC and LDL levels and decreased HDL levels. Vitamin supplementation demonstrated a beneficial effect by reducing TC, LDL, and TG levels, although it had minimal impact on HDL.

Effect of vitamin D3 on Oxidative stress and lipid levels

The control sample showed a moderate level of oxidative stress in the absence of Vitamin D3 (0.557 nmol/ml), which was reduced to 0.20 nmol/ml upon Vitamin D₃ treatment. In the diabetic sample, a significantly elevated oxidative stress level (1.04 nmol/ml) was observed, which markedly decreased to 0.14 nmol/ml after Vitamin D3 inoculation. The prolonged diabetic sample exhibited a moderately high oxidative stress level (0.71 nmol/ml) in the absence of Vitamin D3; however, data for the treated group was not available. Lipid levels were found to be higher in the diabetic sample (0.652 g) compared to the control (0.225 g), indicating altered lipid metabolism under diabetic conditions. The results clearly demonstrate that oxidative stress is elevated in diabetic conditions and is associated with increased lipid levels. Vitamin D3 supplementation resulted in a significant reduction in MDA levels in both control and diabetic samples, indicating its protective antioxidant role. The reduction was more pronounced in the diabetic sample, suggesting that Vitamin D3 is particularly effective under conditions of increased oxidative stress.

Conclusion

The study's In vitro component verified that diabetes is linked to serious disruptions in lipid metabolism. When compared to the healthy control, the diabetic sample showed lower levels of high-density lipoprotein (HDL) and higher levels of total cholesterol (TC), triglycerides (TG), and lowdensity lipoprotein (LDL). These results are in line with diabetic dyslipidaemia, which is a significant risk factor for heart problems (American Diabetes Association, 2024; Goldberg, 2001) [1,4] . The effective isolation of lipids was guaranteed by the use of the chloroform-methanol extraction procedure, and the results' dependability was increased by the controlled experimental conditions that preserved the samples' integrity (Folch et al., 1957) [3] .

In vitro, vitamin D3 treatment showed a positive modulatory effect on lipid markers. In treated samples, there was an increase in HDL and a decrease in TC, TG, and LDL levels. These results imply that vitamin D3 is crucial for enhancing lipid metabolism, potentially via mechanisms such increased insulin sensitivity, control of lipid-metabolizing enzymes, and decreased inflammatory reactions. (Pittas et al., 2007; Pilz et al., 2011) [10,9] . The study's In vivo component offered therapeutically significant insights into how vitamin supplementation and medication support work together to manage brain problems linked to long-term diabetes. Over the course of three months under close observation, the chosen subject-a 75year-old patient with long-term diabetes who showed signs of neurotransmitter imbalance-was given a combination of vitamins, including Vitamin D3, Vitamin B complex, and Vitamin C, in addition to prescription drugs like Petril-B and Nexiton (Kennedy, 2016; Harrison and May, 2009; Grant, 2011) [20,19,5] . The patient's clinical condition significantly improved after the supplementing time. Clarity, memory recall, and attention span all improved as a result of improved cognitive function. Anxiety, impatience, and emotional swings decreased, improving mood stability. Additionally, there was an improvement in neuromuscular coordination, which suggests increased nerve-muscle communication. A general improvement in everyday functioning and quality of life was shown by behavioural changes. (Biessels and Reagan, 2015; Kennedy, 2016; Maritim et al., 2003) [2,20,3] .

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