l-carnitine as a Potential Additive in Blood Storage Solutions: A Study on Erythrocytes

Cytoprotective effect of l-carnitine against mancozeb-induced oxidative damage in human erythrocytes

Mancozeb is a commonly used fungicide that protects crops from numerous fungal pathogens. However, due to its widespread application, mancozeb has emerged as a significant human health hazard. Mancozeb causes oxidative damage to human cells, including erythrocytes. In this study, we have investigated the cytoprotective potential of the dietary antioxidant, l-carnitine, on mancozeb-induced oxidative damage in human erythrocytes. Incubation of erythrocytes with 100 μM mancozeb for 24 h caused a substantial elevation of markers of hemoglobin, lipid and protein oxidation. Intracellular levels of reactive oxygen and nitrogen species were considerably increased, and the antioxidant defense system of erythrocytes was severely compromised. Several enzymes catalyzing vital metabolic processes in erythrocytes were significantly inhibited. Mancozeb damaged the plasma membrane, increasing osmotic fragility and cell lysis. Membrane damage resulted in morphological transformation of the normal biconcave erythrocytes to echinocytes and stomatocytes. Erythrocytes incubated with l-carnitine (100-750 μM) for 2 h prior to mancozeb treatment showed a marked reduction in oxidative damage. l-carnitine effectively neutralized free radicals and reactive species, thereby significantly diminishing oxidative stress. The activities of antioxidant and metabolic enzymes were also restored. Preincubation with l-carnitine stabilized the erythrocyte membrane and maintained its standard biconcave shape. Incubation of erythrocytes with l-carnitine alone did not alter any of the above parameters. Thus, l-carnitine can serve as an effective protectant against pesticide-induced cytotoxicity in human erythrocytes.

Attenuation of Oxidative Stress in Erythrocytes Stored with Vitamin C and l-Carnitine in Additive Solution-7

Background: Blood transfusion has advanced toward component therapy for specific requirements during trauma and surgery. Oxidative stress is induced in erythrocytes during storage. Hence, antioxidants as additives can be employed to counteract oxidative stress and enhance antioxidant defenses. Therefore, this study investigates the combinatorial effects of vitamin C and l-carnitine on erythrocytes during storage. Methodology: Erythrocyte samples were categorized into control and experimental groups-vitamin C (10 mM) and l-carnitine (10 mM) and stored under blood bank conditions (at 4°C) for 35 days. Hemoglobin (Hb), antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT] and glutathione peroxidase [GPX]), lipid peroxidation products (conjugate dienes and thiobarbituric acid reactive substances [TBARSs]), protein oxidation products, metabolic markers (glucose, lactate dehydrogenase), glutathione (GSH), superoxides, and hemolysis were assessed at weekly intervals. Results: SOD activity increased on day 7 in the controls, whereas it increased on days 7 and 14 in the experimental groups. CAT activity increased on day 35 in both the groups. GPX activity increased on day 7 in the controls. Hb levels decreased on days 14 and 35 in the controls and on day 35 in the experimental groups. Hemolysis increased from day 7 onward in both the groups. Protein oxidation products were maintained throughout the storage. GSH levels increased on day 21 in the controls and on days 14 and 21 in the experimental groups. Superoxides and conjugate dienes decreased from day 14 in both the groups. TBARSs decreased on day 7 in the experimental groups. Conclusion: Vitamin C and l-carnitine have synergistically enhanced the efficacy of stored erythrocytes in terms of Hb, antioxidant enzymes, and lipid peroxidation.

L-Carnitine and Male Fertility: Is Supplementation Beneficial?

L-Carnitine, a natural antioxidant found in mammals, plays a crucial role in the transport of long-chain fatty acids across the inner mitochondrial membrane. It is used as a nutritional supplement by professional athletes, improving performance and post-exercise recovery. Additionally, its therapeutic applications, including those in male infertility, have been investigated, as it may act as a defense mechanism against the excessive production of reactive oxygen species (ROS) in the testis, a process that can lead to sperm damage. This effect is achieved by enhancing the expression and activity of enzymes with antioxidant properties. Nevertheless, the mechanisms underlying the benefits of L-Carnitine remain unknown. This review aims to consolidate the current knowledge about the potential benefits of L-Carnitine and its role in male (in)fertility. Considering in vitro studies with Sertoli cells, pre-clinical studies, and investigations involving infertile men, a comprehensive understanding of the effects of L-Carnitine has been established. In vitro studies suggest that L-Carnitine has a direct influence on somatic Sertoli cells, improving the development of germ cells. Overall, evidence supports that L-Carnitine can positively impact male fertility, even at a relatively low dose of 2 g/day. This supplementation enhances sperm parameters, regulates hormone levels, reduces ROS levels, and subsequently improves fertility rates. However, further research is needed to elucidate the underlying mechanisms and establish optimal doses. In conclusion, the role of L-Carnitine in the field of male reproductive health is highlighted, with the potential to improve sperm quality and fertility.

Artemisinin and l-carnitine combination therapy alters the erythrocytes redox status

Hematopoiesis is a sensitive target of artemisinin (ART) and its derivatives, and hemolysis is one of their commonly reported side effects. l-carnitine (LC), an amino acid derivative involved in lipid metabolism, is beneficial for hematological parameters. Sixty adult laboratory mice were randomly divided into six groups. Group I (control) received saline and corn oil; groups II and III received therapeutic (50 mg/kg) and toxic (250 mg/kg) doses of ART, respectively; groups IV and V received 370 mg/kg LC along with the 50 and 250 mg/kg ART, respectively; and group VI received 370 mg/kg LC. Drugs were administered orally for 7 consecutive days. The erythrocyte glucose 6-phosphate dehydrogenase (G6PD), catalase (CAT), and peroxidase (POX) activity, and the reduced glutathione (GSH) level were assessed by colorimetric methods. ART reduced the G6PD activity both at therapeutic and toxic doses. The therapeutic dose of ART reduced the CAT activity and the GSH level, nonsignificantly. The toxic dose of ART reduced the CAT activity and increased the POX activity. LC reduced the G6PD, CAT, and POX activities and increased GSH level. The therapeutic dose of ART and LC showed synergy in reducing the G6PD activity. LC and ART combination reduced POX activity and increased GSH level without any significant effect on the CAT activity. Inhibition of G6PD may be a potentially new mechanism of ART action. Coadministration of LC with ART or following treatment with ART may have protective effects on erythrocytes.

Effects of L-carnitine on the erythrocytes of stored human blood

OBJECTIVES

This study aimed to assess the effects of L-carnitine on oxidative stress in human erythrocytes during storage.

BACKGROUND

Using antioxidants as components of blood storage solutions may combat the effects of storage-induced oxidative stress on erythrocytes.

METHODS

Blood from male adults was stored at 4 °C for 55 days in citrate phosphate dextrose adenine solution, without L-carnitine (Control) and with L-carnitine as an additive (at concentrations of 10, 30 and 60 mM - Experiments). Every fifth day, erythrocyte markers (morphology, count, haemoglobin, haemolysis and osmotic fragility), antioxidant defences (antioxidant enzymes and total antioxidant capacity) and oxidative stress markers (superoxides, lipid peroxidation and protein oxidation products) were analysed.

RESULTS

Oxidative damage was observed in controls (day 25 onwards) and in experiments (day 35 onwards). L-carnitine (10 and 30 mM) protected erythrocytes from damage up to day 35 by maintaining haemoglobin and lipid peroxidation, assisting antioxidant enzymes and increasing antioxidant capacity by elevating sulfhydryls and ascorbic acid. L-carnitine was beneficial in prolonging storage up to 55 days but could not prevent oxidative damage completely in terms of haemolysis and osmotic fragility.

CONCLUSIONS

L-carnitine ameliorated oxidative stress, but combinations with other antioxidants may provide comprehensive protection to erythrocytes during storage.

Influence of L-Carnitine on Stored Rat Blood: A Study on Plasma

Objective:

Plasma acts as a good indicator of oxidative stress in blood. L-Carnitine is an antioxidant that reduces metabolic stress in cells, thereby providing a protective effect against oxidative stress (OS). L-Carnitine as an additive in storage has not been explored. Thus, this study attempts to analyze the role of L-carnitine in blood storage solution, citrate phosphate dextrose adenine (CPDA)-1, through OS markers including antioxidant enzymes, lipid peroxidation, and protein oxidation.

Materials and Methods:

Blood was collected from male Wistar rats and stored in CPDA-1 solution with L-carnitine (10 mM, 30 mM, and 60 mM: groups LC 10, LC 30, and LC 60, respectively) and without L-carnitine (control group). Plasma was isolated every 5th day and the OS markers were analyzed.

Results:

Superoxide dismutase (SOD) and sulfhydryl (SH) increased over storage in controls, LC 30, and LC 60. Catalase increased in LC 30 and LC 60 during storage. Thiobarbituric acid reactive substances (TBARS) and protein carbonyl (PrC) levels in all groups increased initially and reduced towards the end of storage. SOD and SH levels were maintained while TBARS and PrC levels increased in LC 10.

Conclusion:

L-Carnitine was beneficial in terms of increased antioxidant capacity and SH and decreased lipid peroxidation. This forms the basis for further studies on L-carnitine as a constituent in storage solutions.