The contribution of oxidative stress to platelet senescence during storage

The effect of modulating platelet reactive oxygen species by the addition of antioxidants to prevent clearance of cold-stored platelets

BACKGROUND

It is known that the rapid clearance of cold-stored platelets is attributed to various storage lesions, including an abnormal increase in reactive oxygen species when platelets are exposed to cold temperatures. As an antioxidant, N-acetylcysteine exhibits some significant effects on scavenging various reactive oxygen species and inhibiting cell damage and apoptosis.

AIMS

This study aimed to investigate the effects of N-acetylcysteine on reducing reactive oxygen species production and protecting cold-stored platelets from phagocytosis and clearance, and to determine the optimal concentration of N-acetylcysteine.

METHODS

Platelet concentrates were divided into three groups: room-temperature-stored platelets, cold-stored platelets, and cold-stored platelets with the addition of different concentrations of N-acetylcysteine. After five days of storage, reactive oxygen species production, lipid peroxidation levels, activation marker expressions, GPIb/ɑ desialylation with exposure of glycan residues and other quality parameters of platelets were measured and compared between the groups. Phagocytosis of platelets was detected by phorbol 12-myristate 13-acetate-activated THP-1 or Hep G2 cells. Moreover, the recovery of infused platelets was measured in severe combined immunodeficient mice at different timepoints.

RESULTS

After 5 days of storage, cytoplasmic reactive oxygen species significantly increased in chilled compared to non-chilled platelets; they were notably reduced with the addition of N-acetylcysteine, particularly at a concentration of 5 mM. Compared with chilled platelets, the P-selectin and phosphatidylserine expressions, as well as exposure of GPIb/ɑ glycan residues, were significantly reduced with 5 mM of N-acetylcysteine. Phagocytosis of platelets by THP-1 or Hep G2 cells was significantly lower in 5 mM of N-acetylcysteine compared to cold-stored platelets without N-acetylcysteine.

CONCLUSIONS

This study demonstrated correlations between reactive oxygen species production and their pro-oxidant effects on platelet clearance after cold storage. The addition of N-acetylcysteine at an appropriate concentration do not only protects chilled platelets from storage lesions caused by reactive oxygen species overproduction but also prevents platelet phagocytosis in vitro and clearance in vivo, thereby extending circulating time.

Oxidative modulations in platelets stored in SSP+, PAS-G and Tyrode's buffer: a comparative analysis

BACKGROUND

Platelet additive solutions (PASs) improve the efficacy of stored platelets. Oxidative stress causes storage lesions and platelet functions deteriorate. Studies assessing the influence of oxidative stress on platelets stored in PASs are limited. This study compares variations in platelets in different storage solutions (SSP+, PAS-G and Tyrode's buffer).

METHODS

Platelets isolated from the blood of Wistar rats were resuspended in SSP+, PAS-G and Tyrode's buffer and stored for seven days at 22 °C. The markers of platelet metabolism, function, oxidative stress, antioxidant status and viability were analyzed on Days 1, 3, 5 and 7 of storage.

MAIN RESULTS

SSP+ is associated with platelet function, viability and antioxidant defenses (SOD, CAT and GSH); it decreased primary lipid peroxidation products and maintained the susceptible protein groups in reduced state. Platelet function, antioxidant defenses such as SOD and GSH improved, and lipids and thiols were protected from oxidation in PAS-G. SOD and GSH increased, and lipids and thiols were preserved in Tyrode's buffer.

CONCLUSION

SSP+ and PAS-G are more effective in maintaining platelet efficacy till Day 7 compared to Tyrode's buffer. Thus, PAS-G and SSP+ are better than Tyrode's buffer in terms of platelet responses to oxidative stress during storage. This is the first comparative account on the influence of PASs (SSP+, PAS-G and Tyrode's buffer) on platelets in altering oxidative stress. It provides a comprehensive view of the differential responses of platelets in PASs.

Liposomal Resveratrol Alleviates Platelet Storage Lesion via Antioxidation and the Physical Buffering Effect

Platelet transfusion is essential in the treatment of platelet-related diseases and the prevention of bleeding in patients with surgical procedures. Platelet transfusion efficacy and shelf life are limited mainly by the development of platelet storage lesion (PSL). Mitigating PSL is the key to prolonging the platelet shelf life and reducing wastage. Excess intracellular reactive oxygen species (ROS) are one of the main factors causing PSL. In this study, we explored a nanomedicine strategy to improve the quality and functions of platelets in storage. Resveratrol (Res), a natural plant product, is known for its antioxidative effect. However, medical applications of Res are limited due to its low water solubility and stability. Therefore, we used a resveratrol-loaded liposomal system (Res-Lipo) to better utilize the antioxidant effect of the drug. This study aimed to evaluate the effect of Res-Lipo on platelet oxidative stress and alleviation of PSL during the storage time. Res-Lipo scavenged intracellular ROS and inhibited platelet apoptosis and activation during storage. Res-Lipo not only maintained mitochondrial function but also improved platelet aggregation in response to adenosine 5'-diphosphate. These results revealed that Res-Lipo ameliorated PSL and prolonged the platelet survival time in vivo. The strategy provides a potential method for extending the platelet storage time and might be considered a potential and safe additive to alleviate PSL.

Conversion of senescent cartilage into a pro-chondrogenic microenvironment with antibody-functionalized copper sulfate nanoparticles for efficient osteoarthritis therapy

The development of osteoarthritis (OA) correlates with the expansion of senescent cells in cartilage, which contributes to an inflammatory microenvironment that accelerates matrix degradation and hampers cartilage generation. To address OA, we synthesized small copper sulfide nanoparticles functionalized with anti-beta-2-microglobulin antibodies (B2M-CuS NPs) that catalyze the formation of toxic •OH from H2O2 via peroxidase-like activity. These B2M-CuS NPs are specifically targeted to induce apoptosis in senescent chondrocytes while showing no toxicity toward normal chondrocytes. Furthermore, B2M-CuS NPs enhance the chondrogenesis of normal chondrocytes. Thus, B2M-CuS NPs can effectively treat OA by clearing senescent chondrocytes and promoting cartilage regeneration after intra-articular injection into the knee joints of surgery-induced OA mice. This study uses smart nanomaterials to treat OA with a synergistic strategy that both remodels senescent cartilage and creates a pro-chondrogenic microenvironment.

Resveratrol reduces platelet storage lesion by preventing free mitochondrial DNA (mtDNA) accumulation in platelet concentrates during storage

Platelet activation and mitochondrial damage are among the crucial events leading to the quality reduction of platelet concentrates (PCs) during preparation and storage, called platelet storage lesion. Platelet activation results in the clearance of transfused platelets. Oxidative stress and platelet activation trigger mitochondrial DNA (mtDNA) release into the extracellular milieu which is associated with adverse transfusion reactions. Therefore, we aimed to investigate the effects of resveratrol, an antioxidant polyphenol, on platelet activation markers and mtDNA release. Ten PCs were divided equally into two bags each, one of them was allocated to the control group (n = 10) and another to the case group (resveratrol-treated, n = 10). Free mtDNA level and CD62P (P-selectin) expression level were measured by absolute quantification Real-Time PCR, and flow cytometry on days 0 (the receiving day), 3, 5, and 7 of storage respectively. Moreover, Lactate dehydrogenase (LDH) enzyme activity, pH, platelet count, mean platelet volume (MPV), and platelet distribution width (PDW) were assessed as well. Treatment of PCs with resveratrol can significantly decrease mtDNA release during storage compared to the control. In addition, platelet activation was significantly mitigated. We also observed significantly lower MPV, PDW, and LDH activity in resveratrol-treated PCs compared to the control group on days 3, 5, and 7. Furthermore, resveratrol maintained the pH of PCs on day 7. Resveratrol diminished free mtDNA and maintained biochemical parameters in PCs, possibly by reducing platelet activation. Therefore, resveratrol might be a possible additive solution for improving the quality of stored PCs.

Platelet storage: Progress so far

There is a crucial need for platelet transfusion during an emergency-surgery and treatment of platelet disorders. The unavailability of donors has furthermore increased the demand for platelet storage. Platelets have limited shelf life due to bacterial contamination and storage lesions. Temperature, materials, oxygen availability, media, platelet processing and manufacturing methods influence the platelet quality and viability during storage. The conception of various platelet additive solutions along with the advent of plastic storage during the 1980s led to enormous developments in platelet storage strategies. Cold storage of platelets gained attention despite its inability to contribute to platelet survival post-transfusion as it offers faster haemostasis. Several developments in platelet storage strategies over the years have improved the quality and shelf-life of stored platelets. Despite the progress, the efficacy of platelets during storage beyond a week has not been achieved. Antioxidants as additives have been explored in platelet storage and have proven to enhance the efficacy of platelets during prolonged storage. However, the molecular interactions of antioxidants in platelets can provide a better understanding of their mechanism of action. Optimization of dosage concentrations of antioxidants is also a critical parameter to be considered as they tend to exhibit toxicity at certain levels. This review provides comprehensive insights into the critical factors affecting platelet storage and the evolution of platelet storage. It also emphasizes the role of antioxidants as additives in platelet storage solutions and their future prospects towards better platelet banking.

CPT2 K79 Acetylation Regulates Platelet Lifespan

CPT2 K79 acetylation caused by NAD⁺ exhaustion and Sirt3 dysfunction resulted in LCAC accumulation and platelet damage.

Blocking acylcarnitine generation with AMPK or CPT1 inhibitors, Sirt3 agonists, and antioxidants retarded platelet storage lesion.

The short life span of platelets is a major challenge to platelet transfusion services because of the lack of effective intervention. Here, we found that the accumulation of long-chain acylcarnitines (LCACs) is responsible for mitochondrial damage and platelet storage lesion. Further studies showed that the blockade of fatty acid oxidation and the activation of AMP-activated protein kinase (AMPK)/acetyl-CoA carboxylase/carnitine palmitoyltransferase 1 (CPT1) pathways that promote fatty acid metabolism are important reasons for the accumulation of LCACs. The excessive accumulation of LCACs can cause mitochondrial damage and a short life span of stored platelets. The mechanism study elucidated that NAD⁺ exhaustion and the subsequent decrease in sirtuin 3 (Sirt3) activity caused an increase in the level of CPT2 K79 acetylation, which is the primary cause of the blockade of fatty acid oxidation and the accumulation of LCACs. Blocking LCAC generation with the inhibitors of AMPK or CPT1, the agonists of Sirt3, and antioxidants tremendously retarded platelet storage lesion in vitro and prolonged the survival of stored platelets in vivo posttransfusion with single or combined use. In summary, we discovered that CPT2 acetylation attenuates fatty acid oxidation and exacerbates platelet storage lesion and may serve as a new target for improving platelet storage quality.

Protein Concentrations in Stored Pooled Platelet Concentrates Treated with Pathogen Inactivation by Amotosalen Plus Ultraviolet a Illumination

Platelet granules contain a diverse group of proteins. Upon activation and during storage, platelets release a number of proteins into the circulation or supernatant of stored platelet concentrate (PC). The aim of this work was to investigate the effect of pathogen inactivation (PI) on a selection of proteins released in stored platelets. Materials and Methods: PCs in platelet additive solution (PAS) were produced from whole blood donations using the buffy coat (BC) method. PCs in the treatment arm were pathogen inactivated with amotosalen and UVA, while PCs in the second arm were used as an untreated platelet control. Concentrations of 36 proteins were monitored in the PCs during storage. Results: The majority of proteins increased in concentration over the storage period. In addition, 10 of the 29 proteins that showed change had significantly different concentrations between the PI treatment and the control at one or more timepoints. A subset of six proteins displayed a PI-related drop in concentration. Conclusions: PI has limited effect on protein concentration stored PC supernatant. The protein’s changes related to PI treatment with elevated concentration implicate accelerated Platelet storage lesion (PSL); in contrast, there are potential novel benefits to PI related decrease in protein concentration that need further investigation.

Some Molecular and Cellular Stress Mechanisms Associated with Neurodegenerative Diseases and Atherosclerosis

Chronic stress is a combination of nonspecific adaptive reactions of the body to the influence of various adverse stress factors which disrupt its homeostasis, and it is also a corresponding state of the organism's nervous system (or the body in general). We hypothesized that chronic stress may be one of the causes occurence of several molecular and cellular types of stress. We analyzed literary sources and considered most of these types of stress in our review article. We examined genes and mutations of nuclear and mitochondrial genomes and also molecular variants which lead to various types of stress. The end result of chronic stress can be metabolic disturbance in humans and animals, leading to accumulation of reactive oxygen species (ROS), oxidative stress, energy deficiency in cells (due to a decrease in ATP synthesis) and mitochondrial dysfunction. These changes can last for the lifetime and lead to severe pathologies, including neurodegenerative diseases and atherosclerosis. The analysis of literature allowed us to conclude that under the influence of chronic stress, metabolism in the human body can be disrupted, mutations of the mitochondrial and nuclear genome and dysfunction of cells and their compartments can occur. As a result of these processes, oxidative, genotoxic, and cellular stress can occur. Therefore, chronic stress can be one of the causes forthe occurrence and development of neurodegenerative diseases and atherosclerosis. In particular, chronic stress can play a large role in the occurrence and development of oxidative, genotoxic, and cellular types of stress.

In vivo assessment of anticoagulant and antiplatelet effects of Syzygium cumini leaves extract in rabbits

Background

Syzygium cumini (L.) Skeels. is one of the very popular traditionally used medicinal plants with numerous pharmacological activities including antioxidant, hypoglycemic and anti-inflammatory. However, actions of S. cumini on blood coagulation and other parameters of blood were poorly pharmacologically studied. Therefore, aim of this present investigation is to examine the effects of methanolic extract of S. cumini on blood coagulation and anticoagulation factors in healthy white albino rabbits at different doses.

Methods

Blood samples were drawn twice during this study and biochemical assays were performed to determine the effect on different parameters such as coagulation, anticoagulation, hematological, Protein C (PC) and thrombin antithrombin (TAT) complex and platelet aggregation.

Results

The results showed significant increase in RBCs, hemoglobin, hematocrit and platelets counts up to 1.4 × 10³/cm, 2.2 g/dl, 6%, 248.2 × 10³/cm respectively. While, thrombin and bleeding time were also prolonged in dose dependent manner which is highly significant (p ≤ 0.005) as compared to control. Similarly, highly significantly increased (p ≤ 0.005) in levels of protein C, thrombin antithrombin complex at dose of 500 mg/kg were observed. Whereas, levels of platelets aggregation and fibrinogen were decreased at high doses.

Conclusion

The obtained findings of hematological and coagulation tests concludes possibly S. cumini possess anticoagulant and antiplatelet effects.