A novel approach for in vitro meat production

Transdifferentiation of fibroblasts into muscle cells to constitute cultured meat with tunable intramuscular fat deposition

Current studies on cultured meat mainly focus on the muscle tissue reconstruction in vitro, but lack the formation of intramuscular fat, which is a crucial factor in determining taste, texture, and nutritional contents. Therefore, incorporating fat into cultured meat is of superior value. In this study, we employed the myogenic/lipogenic transdifferentiation of chicken fibroblasts in 3D to produce muscle mass and deposit fat into the same cells without the co-culture or mixture of different cells or fat substances. The immortalized chicken embryonic fibroblasts were implanted into the hydrogel scaffold, and the cell proliferation and myogenic transdifferentiation were conducted in 3D to produce the whole-cut meat mimics. Compared to 2D, cells grown in 3D matrix showed elevated myogenesis and collagen production. We further induced fat deposition in the transdifferentiated muscle cells and the triglyceride content could be manipulated to match and exceed the levels of chicken meat. The gene expression analysis indicated that both lineage-specific and multifunctional signalings could contribute to the generation of muscle/fat matrix. Overall, we were able to precisely modulate muscle, fat, and extracellular matrix contents according to balanced or specialized meat preferences. These findings provide new avenues for customized cultured meat production with desired intramuscular fat contents that can be tailored to meet the diverse demands of consumers.

Could insects be an alternative food source? A comprehensive review

According to the United Nations, more than 800 million people are exposed to starvation. It is predicted that the world population will face much more serious starvation for reasons such as global warming, diseases, economic problems, rapid urbanization, and destruction of agricultural areas and water resources. Thus, there are significant hesitations about the sustainability of food resources, and the search for alternative food sources has increased. One of the leading alternative food sources is insects. Although the use of edible insects has been accepted in some areas of the world, entomophagy is not preferred in some countries due to sociocultural conditions, health concerns, neophobia, and entomophobia. Many people do not accept the direct consumption of raw insects, but insects can be transformed into more preferred forms by using different cooking techniques. Some ground edible insects are satisfactory in terms of nutritional value and have a reasonable level of acceptability when added to products such as bread, tortilla, and pasta in varying percentages. The world market value of edible insects was estimated to be US$3.2 million in 2021 and US$17.6 billion in 2032. In this review, the current and future situation of insects as an alternative food source is comprehensively discussed.

Tuning the efficacy of decellularized apple by coating with alginate/gelatin to behave as a bioscaffold for cultured meat production

Substantial efforts are underway to tackle the current challenges of sustainability and environmental impacts linked to orthodox animal agriculture. This had led to advancement in food innovation guiding the fabrication of edible scaffolds based cultured meat. This current research work aims to develop and validate a new approach in fabricating a 3D porous scaffold of decellularized apple coated with a polymer mixture of gelatin/alginate for cultivated meat production. The fabricated noncoated (A) and coated (CA) 3D scaffolds presented different ratios of pore sizes with the medium-sized pores (100-250 µm) being higher in the case of CA. The water absorption capacity of CA (∼64 %) was almost two folds compared to A (∼31 %) with delayed digestion in the presence of gastric simulated juice with or without pepsin. Both the scaffolds showed the capability to adhere and proliferate muscle satellite cells as single cell culture and muscle satellite along with NIH/3T3 fibroblast cells as co-culture. However, the CA scaffolds showed enhanced capability to adhere and proliferate the two cell lines on its surface compared to A. This work demonstrates an efficient way to fabricate decellularized plant scaffolds with high potential to be used in the production of cultured meat for the food industry.

Advancing our understanding of bioreactors for industrial-sized cell culture: health care and cellular agriculture implications

Bioreactors are advanced biomanufacturing tools that have been widely used to develop various applications in the fields of health care and cellular agriculture. In recent years, there has been a growing interest in the use of bioreactors to enhance the efficiency and scalability of these technologies. In cell therapy, bioreactors have been used to expand and differentiate cells into specialized cell types that can be used for transplantation or tissue regeneration. In cultured meat production, bioreactors offer a controlled and efficient means of producing meat without the need for animal farming. Bioreactors can support the growth of muscle cells by providing the necessary conditions for cell proliferation, differentiation, and maturation, including the provision of oxygen and nutrients. This review article aims to provide an overview of the current state of bioreactor technology in both cell therapy and cultured meat production. It will examine the various bioreactor types and their applications in these fields, highlighting their advantages and limitations. In addition, it will explore the future prospects and challenges of bioreactor technology in these emerging fields. Overall, this review will provide valuable insights for researchers and practitioners interested in using bioreactor technology to develop innovative solutions in the biomanufacturing of therapeutic cells and cultured meat.

Towards a More Realistic In Vitro Meat: The Cross Talk between Adipose and Muscle Cells

According to statistics and future predictions, meat consumption will increase in the coming years. Considering both the environmental impact of intensive livestock farming and the importance of protecting animal welfare, the necessity of finding alternative strategies to satisfy the growing meat demand is compelling. Biotechnologies are responding to this demand by developing new strategies for producing meat in vitro. The manufacturing of cultured meat has faced criticism concerning, above all, the practical issues of culturing together different cell types typical of meat that are partly responsible for meat’s organoleptic characteristics. Indeed, the existence of a cross talk between adipose and muscle cells has critical effects on the outcome of the co-culture, leading to a general inhibition of myogenesis in favor of adipogenic differentiation. This review aims to clarify the main mechanisms and the key molecules involved in this cross talk and provide an overview of the most recent and successful meat culture 3D strategies for overcoming this challenge, focusing on the approaches based on farm-animal-derived cells.

Development of serum-free and grain-derived-nutrient-free medium using microalga-derived nutrients and mammalian cell-secreted growth factors for sustainable cultured meat production

Considering the amount of global resources and energy consumed, and animal welfare issues associated with traditional meat production, cultured meat production has been proposed as a solution to these problems and is attracting worldwide attention. Cultured meat is produced by culturing/proliferating animal muscle cells in vitro. This process requires significant amounts of culture medium, which accounts to a major portion of the production cost. Furthermore, it is composed of nutrients derived from grains and heterotrophic microorganisms and fetal bovine serum (FBS), which will impact the sustainability of cultured meat in future. Here, we developed a novel medium containing nutrients extracted from microalga and cell-secreted growth factors. First, rat liver epithelial RL34 cells were cultured by adding Chlorella vulgaris extract (CVE) to inorganic salt solution. The supernatant, containing the RL34 cell-secreted growth factors, was used as the conditioned medium (CM). This CM, with CVE added as a nutrient source, was applied to primary bovine myoblast cultures. This serum-free and grain-derived-nutrient-free medium promoted the proliferation of bovine myoblasts, the main cell source for cultured beef. Our findings will allow us to take a major step toward reducing production costs and environmental impacts, leading to an expansion of the cultured meat market.

Clean meat: techniques for meat production and its upcoming challenges

Meat is traditionally obtained by sacrificing the animals. It is considered as one of the richest sources of proteins. There is an increasing demand for meat worldwide. It may not be possible to fulfill this demand for meat in future. Therefore, there is an urgent need to find out the alternative resources for proteins requirement shortly. Clean meat production is one of the best methods to be adopted as an alternative to traditional meat. The word 'clean' signifies that we can procure meat from animals without its monstrous slaughtering. Hence, it is prepared by isolating a single cell and culturing them in controlled growth conditions and medium that mimic the in vivo condition. It is not a brand new technology, but the tools for developing clean meat that mimics real meat have been technologically advanced recently. Many companies have marketed clean meat products worldwide from last five years. And it has been observed that there are mixed responses for its acceptance by consumers. The main driving forces for clean meat production derives from the concerns over environment, animal welfare, public and consumer health aspects of animal production, use of antibiotics in the animal industries, and food security. Since it's an upcoming meat production technology, there are many hurdles and challenges like nutritional attributes, flavor, shape, and structure compared to real meat. It requires many skills and understanding of muscle stem cells' regeneration and their growth under optimized scale-up production conditions. In this paper the complete details about clean meat, types of cells, and techniques used for its production has been discussed on a lab scale.

A Review of the Challenges Facing Global Commercialization of the Artificial Meat Industry

The sustained growth of global meat consumption incentivized the development of the meat substitute industry. However, long-term global commercialization of meat substitutes faces challenges that arise from technological innovation, limited consumer awareness, and an imperfect regulatory environment. Many important questions require urgent answers. This paper presents a review of issues affecting meat substitute manufacturing and marketing, and helps to bridge important gaps which appear in the literature. To date, global research on meat substitutes focuses mainly on technology enhancement, cost reduction, and commercialization with a few studies focused on a regulatory perspective. Furthermore, the studies on meat substitute effects on environmental pollution reduction, safety, and ethical risk perception are particularly important. A review of these trends leads to conclusions which anticipate the development of a much broader market for the meat substitute industry over the long term, the gradual discovery of solutions to technical obstacles, upgraded manufacturing, the persistent perception of ethical risk and its influence on consumer willingness to accept meat substitutes, and the urgent need for constructing an effective meat substitute regulatory system.

A circular cell culture system using microalgae and mammalian myoblasts for the production of sustainable cultured meat

For sustainable production of cultured meat, we propose a novel circular cell culture (CCC) system in which microalgae are used as nutrient supply for the mammalian cell culture and as a waste-medium recycler. Chlorococcum littorale, RL34 hepatocytes, and C2C12 myoblasts were used as cell sources for microalgae, growth factor-producing cells, and muscle cells, respectively. In the first cycle, C2C12 cells were amplified 4.0-fold after 48 h of culture in an RL34 cell-conditioned medium. In the second cycle, C2C12 cells were cultured in the C. littorale culture waste medium to which the C. littorale-derived nutrients were added. The proliferation rates of C. littorale and C2C12 and the nutrient extraction efficiency from C. littorale were the same in the first and second cycles. Therefore, this CCC system, which works without additional grain-derived nutrients and animal sera, will help drastically reduce environmental load, resource/energy consumption, and costs in future cultured meat production.

Perception of Cultured Meat as a Basis for Market Segmentation: Empirical Findings from Croatian Study

Many studies have already addressed the perception of cultured meat, but the segmentation of potential consumers has not been adequately investigated. Based on an online survey in Croatia with 411 valid responses, four socio-demographically characterized segments were identified. The key differentiators between the segments relate to consumers’ moral and ethical concerns about cultured meat and their perceptions of the impact of cultured meat production on the economy. The multinomial logistic regression used to describe the segments found that the segments differed from the reference segment (Concerned) in terms of support for public research and funding of cultured meat, the willingness to consume it, and religiosity. These results help provide deeper insight into the profiles of potential consumers of cultured meat.

On the Intertwining of Cellular Agriculture and Animal Agriculture: History, Materiality, Ideology, and Collaboration

This review essay documents continuities between (industrial) animal agriculture and cellular agriculture and raises key questions about whether or not the technology might be able to deliver on its promise of food system transformation. It traces how industrial history, connections to the livestock industry, and disavowal are extended through the innovation of cellular agriculture. In particular, it is shown that cellular agriculture has had connections to (industrial) animal agriculture since its very beginning and at nearly every step since then. I argue that cellular agriculture can be positioned as the epitome of (industrial) animal agriculture in terms of history, material practices, and ideology. Such a critique of cellular agriculture has become somewhat commonplace but while a number of papers have raised similar concerns individually, there exists no sustained focus on such similarities to make this point holistically. Such connections are important in framing the future of cellular agriculture and the fate of farmed animals and the environment. Carefully considering the continuities between cellular agriculture and animal agriculture is crucial when considering whether promoting cellular agricultural is a prudent approach to addressing problems associated with animal agriculture. The cumulative number and extent of connections covered in this essay leads to questions of who will benefit with the advent of cellular agriculture.

In-vitro meat: a promising solution for sustainability of meat sector

The in-vitro meat is a novel concept in food biotechnology comprising field of tissue engineering and cellular agriculture. It involves production of edible biomass by in-vitro culture of stem cells harvested from the muscle of live animals by self-organizing or scaffolding methodology. It is considered as efficient, environmental friendly, better ensuring public safety and nutritional security, as well as ethical way of producing meat. Source of stem cells, media ingredients, supply of large size bioreactors, skilled manpower, sanitary requirements, production of products with similar sensory and textural attributes as of conventional meat, consumer acceptance, and proper set up of regulatory framework are challenges faced in commercialization and consumer acceptance of in-vitro meat. To realize any perceivable change in various socio-economic and environmental spheres, the technology should be commercialized and should be cost-effective as conventional meat and widely accepted among consumers. The new challenges of increasing demand of meat with the increasing population could be fulfill by the establishment of in-vitro meat production at large scale and its popularization. The adoption of in-vitro meat production at an industrial scale will lead to self-sufficiency in the developed world.

The Epic of In Vitro Meat Production-A Fiction into Reality

Due to a proportionally increasing population and food demands, the food industry has come up with wide innovations, opportunities, and possibilities to manufacture meat under in vitro conditions. The amalgamation of cell culture and tissue engineering has been the base idea for the development of the synthetic meat, and this has been proposed to be a pivotal study for a futuristic muscle development program in the medical field. With improved microbial and chemical advancements, in vitro meat matched the conventional meat and is proposed to be eco-friendly, healthy, nutrient rich, and ethical. Despite the success, there are several challenges associated with the utilization of materials in synthetic meat manufacture, which demands regulatory and safety assessment systems to manage the risks associated with the production of cultured meat. The role of 3D bioprinting meat analogues enables a better nutritional profile and sensorial values. The integration of nanosensors in the bioprocess of culture meat eased the quality assessment throughout the food supply chain and management. Multidisciplinary approaches such as mathematical modelling, computer fluid dynamics, and biophotonics coupled with tissue engineering will be promising aspects to envisage the future prospective of this technology and make it available to the public at economically feasible rates.

Three-dimensional tissue fabrication system by co-culture of microalgae and animal cells for production of thicker and healthy cultured food

OBJECTIVES

"Cultured food" is focused worldwide as "the third stage in meat production system" after hunting and livestock farming, and a sustainable food production system. In this study, we attempted to fabricate a three-dimensional (3-D) tissue by co-cultivation of animal cells with photosynthetic autotrophic microalgae so as to produce thicker and healthy cultured foods.

RESULTS

Metabolism and damage of co-cultured tissues fabricated by microalgae, Chlorella vulgaris (C. vulgaris), and C2C12 cells were compared to monoculture tissues fabricated by C2C12 animal cells alone. Although the metabolism of monoculture tissue showed anaerobic respiration (ratio of lactate production to glucose consumption, LG ratio: 2.01 ± 0.15), that of the co-culture tissue partially changed to efficient aerobic respiration (LG ratio: 1.58 ± 0.14). In addition, the amount of ammonia in the culture media decreased markedly by co-cultivation. The release of lactate dehydrogenase from the thicker tissue was one-seventh in the co-cultivation, showing improved tissue damage. The co-cultivation with microalgae improved the culture condition of thicker tissues, resulting in the fabrication/maintenance of 200-400 µm-thickness tissues. The co-cultured tissue fabricated by microalgae and animal cells was not only rich in nutrients but also enabled thicker tissue fabrication without tissue damage as compared to tissue fabricated by animal cells alone.

CONCLUSIONS

This tissue fabrication system by co-culture of microalgae and animal cells will be a valuable tool for the production of thicker and healthy cultured food.

Panorama and ambiguities of cultured meat: an integrative approach

The purpose of this research was to identify, through a systematic review of the literature, the strengths, weaknesses, threats and opportunities of the production and commercialization of cultured meat, as well as to analyze the challenges to be faced by this new food biotechnology. For this, we analyzed 194 manuscripts published in the Scopus and Web of Science databases that dealt with cultured meat under the perspective of cellular agriculture, employing several nomenclatures. The results indicate that there is still no consensus in the literature about the strengths, weaknesses, threats and opportunities of cultured meat, which constitutes an emerging, multifaceted, and encouraging field of study, and a series of inferences have been made that provide insights into the knowledge analyzed. Finally, we propose an analytical model that combines sub-scenarios from which it becomes possible to understand and anticipate the direction of this new food biotechnology.

Stem cells-derived in vitro meat: from petri dish to dinner plate

Sustainable food supply to the world is possibly the greatest challenge that human civilization has ever faced. Among animal sourced foods, meat plays a starring role in human food chain. Traditional meat production necessitates high proportion of agricultural land, energy and clean water for rearing meat-producing animals; also massive emission of greenhouse gases from the unutilized nutrients of the digestive process into the environment is a major challenge to the world. Also, conventional meat production is associated with evolution and spread of superbugs and zoonotic infections. In vitro meat has the potential to provide a healthy alternative nutritious meal and to avoid the issues associated with animal slaughtering and environmental effects. Stem cell technology may provide a fascinating approach to produce meat in an animal-free environment. Theoretically, in vitro meat can supplement the meat produced by culling the animals and satisfy the global demand. This article highlights the necessity and potential of stem cell-derived in vitro meat as an alternative source of animal protein vis-a-vis the constraints of conventional approaches of meat production.

Cell-Based Meat and Firms’ Environmental Strategies: New Rationales as per Available Literature

Higher demand for meat production and limited inputs, as well as environmental and animal ethics issues, are bringing alternative protein sources to the market, such as cell-based meat (CBM), i.e., meat produced through cell culturing, without involving animal raising and killing. Although the potential social and environmental benefits of the technology have been recently addressed in the blossoming CBM literature, little has been discussed about the possible implications for the environmental strategies of firms that are entering the new cell-based production chain. Thus, drawing on the theoretical framework of competitive environmental strategies and a systematic review of the literature, we discuss prospects for cell-based meat regarding the possible adoption of environmental strategies by firms that are entering the CBM chain. The technology may be considered a potential means for mitigating most of the environmental impacts of large-scale meat production, e.g., extensive land use and greenhouse gas emissions. We discuss how such benefits and consumer attitudes towards cultivated meat could encourage the adoption of environmental strategies by firms, and the roles that value chain firms are likely to play in those strategies in the future.

Critical Perspective of Animal Production Specialists on Cell-Based Meat in Brazil: From Bottleneck to Best Scenarios

Simple Summary

The opinion of professionals involved in animal production is very important to the development of the emerging cell-based meat chain. This paper aims to analyse the perspective of Brazilian veterinarians and animal scientists regarding cell-based meat—women, veterinarians, vegetarians and vegans were more supportive of cell-based meat. The resistance expressed by the professionals seems related to a lack of knowledge and the association of cultivated meat with artificiality, which has a negative connotation. Therefore, higher education and motivation of veterinarians and animal scientists may mitigate the resistance and help these professionals to engage in this new chain for the benefit of the professionals themselves, society, the animals involved and the environment.

Abstract

Recently, many studies regarding consumer perception of cell-based meat have been published. However, the opinion of the professionals involved in animal production also seems relevant. In particular, veterinarians and animal scientists may be important players in the new cell-based meat production, acting as proponents or barriers to this major improvement for farm animal welfare. Therefore, our aim is to analyse the knowledge and perspective of Brazilian veterinarians and animal scientists regarding cell-based meat. Veterinarians (76.8%; 209/272) and animal scientists (23.2%; 63/272) responded to an online survey. Logistic regression, latent class and logit models were used to evaluate objective answers, and the Discourse of the Collective Subject method was used to interpret open-ended answers. Specialists who were women (62.5%; 170/272), veterinarians (76.8%; 209/272), vegetarians (7.0%; 19/272) and vegans (1.1%; 3/272) were more supportive of cell-based meat. Lack of knowledge and the connection with artificiality, the most frequent spontaneous word associated with cell-based meat by all respondents, were the main negative points highlighted. Thus, it seems fundamental to offer higher education to veterinarians and animal scientists regarding cell-based meat, since engaging them with this novel technology may mitigate both the resistance and its negative consequences for the professionals, society, the animals involved and the environment.

Zinc oxide nanoparticles induce apoptosis and autophagy in human ovarian cancer cells

Background

Zinc oxide nanoparticles (ZnO NPs) are frequently used in industrial products such as paint, surface coating, and cosmetics, and recently, they have been explored in biologic and biomedical applications. Therefore, this study was undertaken to investigate the effect of ZnO NPs on cytotoxicity, apoptosis, and autophagy in human ovarian cancer cells (SKOV3).

Methods

ZnO NPs with a crystalline size of 20 nm were characterized with various analytical techniques, including ultraviolet-visible spectroscopy, X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, and atomic force microscopy. The cytotoxicity, apoptosis, and autophagy were examined using a series of cellular assays.

Results

Exposure of cells to ZnO NPs resulted in a dose-dependent loss of cell viability, and the characteristic apoptotic features such as rounding and loss of adherence, enhanced reactive oxygen species generation, and loss of mitochondrial membrane potential were observed in the ZnO NP-treated cells. Furthermore, the cells treated with ZnO NPs showed significant double-strand DNA breaks, which are gained evidences from significant number of γ-H₂AX and Rad51 expressed cells. ZnO NP-treated cells showed upregulation of p53 and LC3, indicating that ZnO NPs are able to upregulate apoptosis and autophagy. Finally, the Western blot analysis revealed upregulation of Bax, caspase-9, Rad51, γ-H₂AX, p53, and LC3 and downregulation of Bcl-2.

Conclusion

The study findings demonstrated that the ZnO NPs are able to induce significant cytotoxicity, apoptosis, and autophagy in human ovarian cells through reactive oxygen species generation and oxidative stress. Therefore, this study suggests that ZnO NPs are suitable and inherent anticancer agents due to their several favorable characteristic features including favorable band gap, electrostatic charge, surface chemistry, and potentiation of redox cycling cascades.

In vitro drug testing based on contractile activity of C2C12 cells in an epigenetic drug model

Skeletal muscle tissue engineering holds great promise for pharmacological studies. Herein, we demonstrated an in vitro drug testing system using tissue-engineered skeletal muscle constructs. In response to epigenetic drugs, myotube differentiation of C2C12 myoblast cells was promoted in two-dimensional cell cultures, but the levels of contractile force generation of tissue-engineered skeletal muscle constructs prepared by three-dimensional cell cultures were not correlated with the levels of myotube differentiation in two-dimensional cell cultures. In contrast, sarcomere formation and contractile activity in two-dimensional cell cultures were highly correlated with contractile force generation of tissue-engineered skeletal muscle constructs. Among the epigenetic drugs tested, trichostatin A significantly improved contractile force generation of tissue-engineered skeletal muscle constructs. Follistatin expression was also enhanced by trichostatin A treatment, suggesting the importance of follistatin in sarcomere formation of muscular tissues. These observations indicate that contractility data are indispensable for in vitro drug screening.

How Growing Complexity of Consumer Choices and Drivers of Consumption Behaviour Affect Demand for Animal Source Foods

Many societies are spoiled for choice when they purchase meat and other livestock products, and around the globe food choice has grown dramatically in the last two decades. What is more, besides the cost and obvious health concerns influencing commodity section, an increasing proportion of choices is made to contribute to the achievement of certain ideals, such as natural resource management, climate change mitigation, animal welfare concerns and personal lifestyle. At the same time, human health considerations are becoming more important for consumption choices as richer societies, and increasingly the urban poor in low- and middle-income countries, face an unprecedented epidemic of over-consumption and associated diet-related non-communicable diseases. Animal source foods are considered significant contributors to this trend. This paper reviews this complicated arena, and explores the range of considerations that influence consumers' preferences for meat and other animal source foods. This paper also argues that deeper drivers of consumption behaviour of many foods may act in opposition to the articulated preferences for choices around animal source food consumption. We review how the returns to different causes are being valued, how emerging metrics are helping to manage and influence consumption behaviours, and draw conclusions regarding options which influence food choice.